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Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work. |
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#1
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greenhouse fan motors
I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years |
#2
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greenhouse fan motors
I have pretty much the same thing in my house. i think the motors are
20 years ould now. Very unlikely to have that many defective motors. I'd look to another problem in mounting or gearing. My first guess would be the motor is too small for the pulley gearing you have, check a new one with an amp meter and see if its pulling more than name plate. If so, change pulleys or go to larger motor. Also possilbe that mounting is poor taking the bearings out. I suppose you'de know it you have low voltage problems at your site. Even occasionally kills motors. Karl |
#3
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greenhouse fan motors
On 7/10/2013 1:14 PM, Bob S wrote:
I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. ... The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico .... I'm agreeing w/ Karl; Emerson isn't just some generic import Chinese no-name; generally while they're assembled in Mexico they're good stuff. A couple of other thoughts -- it's "humid" environment--any chance it's actually condensing environment and you're drowning them in internal condensate? Or are they getting wet from watering system or outside? On mounting, they're not designed for anything except horizontal so if even slightly off that'll be very bad on bearings. Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... What does the vendor say? Surely they can't be happy replacing them this frequently if is under warranty? -- |
#4
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greenhouse fan motors
Do these motors still rotate freely when disconnected, without fan blades?
If they're getting noisy, the sleeve bearings may be failing faster than if these motors were used in less severe indoor indoors. I've seen considerable damage from sleeve bearing failures where the rotors drag on the stator poles. Enclosed motors would very likely last much longer. TEFC totally enclosed motors are available, and typically have ball bearings, so they wouldn't be affected by shaft rust from humidity, or dust wicking the oil out of the bearings. -- WB .......... "Bob S" wrote in message ... I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years |
#5
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greenhouse fan motors
In article , dpb wrote:
Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... Careful with the assumption here - many fans draw _less_ current "restricted" since they move less air, so they are doing less work. Counter-intuitive, but often true. Toss on a meter and try it. I think it was Bruce who mentioned that many people kill furnace blowers by "unrestricting" ductwork to the point that the motors overload... -- Cats, coffee, chocolate...vices to live by Please don't feed the trolls. Killfile and ignore them so they will go away. |
#6
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greenhouse fan motors
On 7/11/2013 8:49 AM, Ecnerwal wrote:
In , wrote: Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... Careful with the assumption here - many fans draw _less_ current "restricted" since they move less air, so they are doing less work. Counter-intuitive, but often true. Toss on a meter and try it. I think it was Bruce who mentioned that many people kill furnace blowers by "unrestricting" ductwork to the point that the motors overload... Depends on whether the restriction raises head pressure significantly... -- |
#7
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greenhouse fan motors
"dpb" wrote in message ... On 7/11/2013 8:49 AM, Ecnerwal wrote: In , wrote: Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... Careful with the assumption here - many fans draw _less_ current "restricted" since they move less air, so they are doing less work. Counter-intuitive, but often true. Toss on a meter and try it. I think it was Bruce who mentioned that many people kill furnace blowers by "unrestricting" ductwork to the point that the motors overload... Depends on whether the restriction raises head pressure significantly... Really on if the blades have stalled. |
#8
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greenhouse fan motors
On 7/11/2013 11:14 AM, Jim Wilkins wrote:
wrote in message ... On 7/11/2013 8:49 AM, Ecnerwal wrote: In , wrote: Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... Careful with the assumption here - many fans draw _less_ current "restricted" since they move less air, so they are doing less work. Counter-intuitive, but often true. Toss on a meter and try it. I think it was Bruce who mentioned that many people kill furnace blowers by "unrestricting" ductwork to the point that the motors overload... Depends on whether the restriction raises head pressure significantly... Really on if the blades have stalled. And if there's increased head resistance, that's a partial stall...or at least more work to keep going against it. LRA is something else again. Too little to really judge; more useful than pic of a similar used motor from and eBay auction would have been pictures of the installation and links to the vendor of the fans and specific model to see what the app looks like as opposed to what the vendor spec'ed and the like. -- -- |
#9
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greenhouse fan motors
"dpb" wrote in message
... On 7/11/2013 11:14 AM, Jim Wilkins wrote: Really on if the blades have stalled. And if there's increased head resistance, that's a partial stall...or at least more work to keep going against it. Just checked with a Kill-A-Watt. A muffin-sized centrifugal blower draws 24W open, 18W with either the intake or exhaust blocked. jsw |
#10
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greenhouse fan motors
On 7/11/2013 12:22 PM, Jim Wilkins wrote:
.... Just checked with a Kill-A-Watt. A muffin-sized centrifugal blower draws 24W open, 18W with either the intake or exhaust blocked. OK, let's recast what I was driving at...you're saying there's no fan curve/as-shipped design point for which it's possible the OP has done something to his ducting or louvers or the like that can result in raising motor load above design so he shouldn't/needn't consider that as a possible root cause/factor? -- |
#11
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greenhouse fan motors
"dpb" wrote in message ... On 7/11/2013 12:22 PM, Jim Wilkins wrote: Just checked with a Kill-A-Watt. A muffin-sized centrifugal blower draws 24W open, 18W with either the intake or exhaust blocked. OK, let's recast what I was driving at...you're saying there's no fan curve/as-shipped design point for which it's possible the OP has done something to his ducting or louvers or the like that can result in raising motor load above design so he shouldn't/needn't consider that as a possible root cause/factor? You said that, not me. I posted only the free-flow and fully blocked readings for a small impedance-protected motor that doesn't represent the loading curve of a larger one. The shape of the blades strongly affects the pressure the fan can produce and the full-load power. You'd need a wattmeter and a gage like this: http://www.dwyer-inst.com/Product/Pr...ges/Series2000 to determine the conditions of that specific installation. I've done it for the cooling fan for vacuum tube and solid-state radio transmitters, not for HVAC. jsw |
#12
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greenhouse fan motors
On 7/11/2013 4:54 PM, Jim Wilkins wrote:
.... ... I posted only the free-flow and fully blocked readings for a small impedance-protected motor that doesn't represent the loading curve of a larger one. The shape of the blades strongly affects the pressure the fan can produce and the full-load power. You'd need a wattmeter and a gage like this: http://www.dwyer-inst.com/Product/Pr...ges/Series2000 to determine the conditions of that specific installation. I've done it for the cooling fan for vacuum tube and solid-state radio transmitters, not for HVAC. So then why are you hounding me over suggesting a possible area for the OP who's looking into motor problems w/ sizable vent fans in a greenhouse? I don't have his fan curve; we don't even have pictures of the installation; all I'm trying to do is give the guy some things to go investigate that could help him get to the bottom of his problem. Certainly he needs far more data than has provided here to have any hope of learning anything specific unless it's truly obvious and then it would seem would already have known... -- |
#13
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greenhouse fan motors
On Thu, 11 Jul 2013 15:13:27 -0500, dpb wrote:
On 7/11/2013 12:22 PM, Jim Wilkins wrote: ... Just checked with a Kill-A-Watt. A muffin-sized centrifugal blower draws 24W open, 18W with either the intake or exhaust blocked. OK, let's recast what I was driving at...you're saying there's no fan curve/as-shipped design point for which it's possible the OP has done something to his ducting or louvers or the like that can result in raising motor load above design so he shouldn't/needn't consider that as a possible root cause/factor? I'd say that sounds right. Short of physical restriction (drag) it is difficult to overload a fan. Restricted air flow COULD possibly cause a fan motor to everheat due to reduced cooling, but not due to increased load. |
#14
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greenhouse fan motors
"dpb" wrote in message
... On 7/11/2013 4:54 PM, Jim Wilkins wrote: dpb" wrote OK, let's recast what I was driving at...you're saying there's no fan curve/as-shipped design point for which it's possible the OP has done something to his ducting or louvers or the like that can result in raising motor load above design so he shouldn't/needn't consider that as a possible root cause/factor? ... I posted only the free-flow and fully blocked readings for a small impedance-protected motor that doesn't represent the loading curve of a larger one. So then why are you hounding me over suggesting a possible area for the OP who's looking into motor problems w/ sizable vent fans in a greenhouse? Hounding you??? jsw |
#15
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greenhouse fan motors
On Wed, 10 Jul 2013 14:09:24 -0500, Karl Townsend wrote: I have pretty much the same thing in my house. i think the motors are 20 years ould now. Very unlikely to have that many defective motors. I'd look to another problem in mounting or gearing. My first guess would be the motor is too small for the pulley gearing you have, check a new one with an amp meter and see if its pulling more than name plate. If so, change pulleys or go to larger motor. Also possilbe that mounting is poor taking the bearings out. I suppose you'de know it you have low voltage problems at your site. Even occasionally kills motors. Karl House voltage is running a little above 120V; low voltage does not seem to be the issue. A meter suggests that the fans are drawing 5.5A to 7A; the latter number is right up toward the nameplate rating but not way over it. Some more background, in case it suggests anything: The salesman who sold us the greenhouse ordered fans with 220V motors for it, even though he had ordered a 120V controller system. He then tried to correct it by ordering new motors only, not complete new fan setups. The motors were changed on-site by the local electrician who was putting the system together. So it is certainly conceivable that the belts may be too loose or too tight. I have no sure-fire way to know what the right tension is; they are tight enough that the belt doesn't flap; the adjustment method is so awkward that having the belts too loose seems to be more likely than too tight. It is also possible that the pulleys are not right in some way. My understanding is that they are the original pulleys from the original motors that were nominally the same HP rating... Some other sort of problem that I haven't thought of is also possible. Bob |
#16
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greenhouse fan motors
On Wed, 10 Jul 2013 15:17:08 -0500, dpb wrote:
On 7/10/2013 1:14 PM, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. ... The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico ... I'm agreeing w/ Karl; Emerson isn't just some generic import Chinese no-name; generally while they're assembled in Mexico they're good stuff. A couple of other thoughts -- it's "humid" environment--any chance it's actually condensing environment and you're drowning them in internal condensate? Or are they getting wet from watering system or outside? On mounting, they're not designed for anything except horizontal so if even slightly off that'll be very bad on bearings. Are they open-flow or is there air blockage via a damper system or discharge/intake louvers or the like? That could drastically raise the flow restriction and raise motor loading if designed/sized solely for open unrestricted flow... What does the vendor say? Surely they can't be happy replacing them this frequently if is under warranty? I am not watering the fans from either side. The installation is a standard type of greenhouse setup; they should not be seeing any more water or condensation than usual. The mounting is slanted. Again, this is the standard way of installing this fan setup, so I assume the vendor selected motors with this in mind. The system has the standard louvers opened by air flow. The vendor does not seem to be happy, but so far they have not offered any ideas... Bob |
#17
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greenhouse fan motors
On Sat, 13 Jul 2013 18:18:23 -0400, Bob S
wrote: On Wed, 10 Jul 2013 14:09:24 -0500, Karl Townsend wrote: I have pretty much the same thing in my house. i think the motors are 20 years ould now. Very unlikely to have that many defective motors. I'd look to another problem in mounting or gearing. My first guess would be the motor is too small for the pulley gearing you have, check a new one with an amp meter and see if its pulling more than name plate. If so, change pulleys or go to larger motor. Also possilbe that mounting is poor taking the bearings out. I suppose you'de know it you have low voltage problems at your site. Even occasionally kills motors. Karl House voltage is running a little above 120V; low voltage does not seem to be the issue. A meter suggests that the fans are drawing 5.5A to 7A; the latter number is right up toward the nameplate rating but not way over it. Some more background, in case it suggests anything: The salesman who sold us the greenhouse ordered fans with 220V motors for it, even though he had ordered a 120V controller system. He then tried to correct it by ordering new motors only, not complete new fan setups. The motors were changed on-site by the local electrician who was putting the system together. So it is certainly conceivable that the belts may be too loose or too tight. I have no sure-fire way to know what the right tension is; they are tight enough that the belt doesn't flap; the adjustment method is so awkward that having the belts too loose seems to be more likely than too tight. It is also possible that the pulleys are not right in some way. My understanding is that they are the original pulleys from the original motors that were nominally the same HP rating... Some other sort of problem that I haven't thought of is also possible. Bob You would have been WAY better off staying with 220 volt motors. This is likely the design problem. A 220 volt motor has exactly half the current and runs much cooler. Surely, your control system just closes a relay (or motor starter relay) so you can run either voltage on the motor. You sound like you're not a EE type, most any competant electrician knows how to easily do this with hardly any rewiring. If you want to stay with the 120 volt setup at this point, my best guess would be to slow the fans down 20 or 25% with a pulley change. Keep in mind your amp test was only at one point in time, there are likely periods where combinations of heat, humidity, and wind are overloading them. Good luck, Karl |
#18
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greenhouse fan motors
On Sun, 14 Jul 2013 03:35:51 -0500, Karl Townsend
wrote: On Sat, 13 Jul 2013 18:18:23 -0400, Bob S wrote: On Wed, 10 Jul 2013 14:09:24 -0500, Karl Townsend wrote: I have pretty much the same thing in my house. i think the motors are 20 years ould now. Very unlikely to have that many defective motors. I'd look to another problem in mounting or gearing. My first guess would be the motor is too small for the pulley gearing you have, check a new one with an amp meter and see if its pulling more than name plate. If so, change pulleys or go to larger motor. Also possilbe that mounting is poor taking the bearings out. I suppose you'de know it you have low voltage problems at your site. Even occasionally kills motors. Karl House voltage is running a little above 120V; low voltage does not seem to be the issue. A meter suggests that the fans are drawing 5.5A to 7A; the latter number is right up toward the nameplate rating but not way over it. Some more background, in case it suggests anything: The salesman who sold us the greenhouse ordered fans with 220V motors for it, even though he had ordered a 120V controller system. He then tried to correct it by ordering new motors only, not complete new fan setups. The motors were changed on-site by the local electrician who was putting the system together. So it is certainly conceivable that the belts may be too loose or too tight. I have no sure-fire way to know what the right tension is; they are tight enough that the belt doesn't flap; the adjustment method is so awkward that having the belts too loose seems to be more likely than too tight. It is also possible that the pulleys are not right in some way. My understanding is that they are the original pulleys from the original motors that were nominally the same HP rating... Some other sort of problem that I haven't thought of is also possible. Bob You would have been WAY better off staying with 220 volt motors. This is likely the design problem. A 220 volt motor has exactly half the current and runs much cooler. Surely, your control system just closes a relay (or motor starter relay) so you can run either voltage on the motor. You sound like you're not a EE type, most any competant electrician knows how to easily do this with hardly any rewiring. If you want to stay with the 120 volt setup at this point, my best guess would be to slow the fans down 20 or 25% with a pulley change. Keep in mind your amp test was only at one point in time, there are likely periods where combinations of heat, humidity, and wind are overloading them. Good luck, Karl Good advice Karl! -- ""Almost all liberal behavioral tropes track the impotent rage of small children. Thus, for example, there is also the popular tactic of repeating some stupid, meaningless phrase a billion times" Arms for hostages, arms for hostages, arms for hostages, it's just about sex, just about sex, just about sex, dumb,dumb, money in politics,money in politics, Enron, Enron, Enron. Nothing repeated with mind-numbing frequency in all major news outlets will not be believed by some members of the populace. It is the permanence of evil; you can't stop it." (Ann Coulter) |
#19
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greenhouse fan motors
On Sun, 14 Jul 2013 03:35:51 -0500, Karl Townsend
wrote: On Sat, 13 Jul 2013 18:18:23 -0400, Bob S wrote: On Wed, 10 Jul 2013 14:09:24 -0500, Karl Townsend wrote: I have pretty much the same thing in my house. i think the motors are 20 years ould now. Very unlikely to have that many defective motors. I'd look to another problem in mounting or gearing. My first guess would be the motor is too small for the pulley gearing you have, check a new one with an amp meter and see if its pulling more than name plate. If so, change pulleys or go to larger motor. Also possilbe that mounting is poor taking the bearings out. I suppose you'de know it you have low voltage problems at your site. Even occasionally kills motors. Karl House voltage is running a little above 120V; low voltage does not seem to be the issue. A meter suggests that the fans are drawing 5.5A to 7A; the latter number is right up toward the nameplate rating but not way over it. Some more background, in case it suggests anything: The salesman who sold us the greenhouse ordered fans with 220V motors for it, even though he had ordered a 120V controller system. He then tried to correct it by ordering new motors only, not complete new fan setups. The motors were changed on-site by the local electrician who was putting the system together. So it is certainly conceivable that the belts may be too loose or too tight. I have no sure-fire way to know what the right tension is; they are tight enough that the belt doesn't flap; the adjustment method is so awkward that having the belts too loose seems to be more likely than too tight. It is also possible that the pulleys are not right in some way. My understanding is that they are the original pulleys from the original motors that were nominally the same HP rating... Some other sort of problem that I haven't thought of is also possible. Bob You would have been WAY better off staying with 220 volt motors. This is likely the design problem. A 220 volt motor has exactly half the current and runs much cooler. Not necessarily. The wattage is the same. 110 just needs heavier wiring to frrd the motor. The motor efficiency is generally pretty much a "wash" Surely, your control system just closes a relay (or motor starter relay) so you can run either voltage on the motor. You sound like you're not a EE type, most any competant electrician knows how to easily do this with hardly any rewiring. If you want to stay with the 120 volt setup at this point, my best guess would be to slow the fans down 20 or 25% with a pulley change. Keep in mind your amp test was only at one point in time, there are likely periods where combinations of heat, humidity, and wind are overloading them. better ratio would likely HELP the situation. It may not be the cure. Also, being BELT DRIVE fans, where is the motor mounted? Is it in the air stream???? Generally motors without venting or fans are used in direct drive fans. Good luck, Karl |
#20
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greenhouse fan motors
On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote:
On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob |
#21
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greenhouse fan motors
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#22
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greenhouse fan motors
On Wednesday, July 17, 2013 2:38:21 PM UTC-4, Bob S wrote:
The pulley change is an interesting idea; I should look into that. I don't know what the curves look like for these propeller fans, but I assume that slowing down the fans would reduce the load on the motors and might cause them to last longer. It would have to make them last a LOT longer to be really useful. Bob The simple calculations shown in the Grainger catalog shows the hp required varies withe Cube of the speed. Their example shows increasing the rpm from 5000 to 6000 requires 1.73 times as much hp. So reducing the speed a little will have a large effect on the hp and life. Dan |
#23
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greenhouse fan motors
Bob S laid this down on his screen :
On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob Bob, I dont think you have ever really told us how these motors fail. You seem to be saying that it might be bearing failure. Then all the discussion about current, voltage etc is wasted. Motor bearings last for decades if rated and cooled correctly. Are yours cool? Is there an undue side load? eg belts too tight. Is the atmosphers corrosive? -- John G |
#24
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Wed, 17 Jul 2013 14:27:18 -0400, Bob S
wrote: On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob 3/4hp? I thought they were 1/3 hp? Running a belt and in the airstream, check. Thats good. No cap? Not very many single phase motors of that size, dont have start/run caps. Sure there arent any inclosed in the fan housing somewhere? http://www.capacitorformotor.com/start_cap.html As for no lube points...I think Id pull down a motor and check. Some indeed are "permanantly lubricated" on the name plate. But I think Id look for either plugs in the end bearing covers or little holes that you can spritz oil into the bearings. Id also take a volt meter and put it on the fan circuit (s) somewhere and check your voltage on both the line and on the input to each fan occasionally. You said that there were several that were running slow...thats either a sign of bearings about to freeze up, shorted windings, low voltage at the motor...or bad run caps or even bad start caps on some..some motors. Get some measurements and you might determine whats going on. Gunner -- ""Almost all liberal behavioral tropes track the impotent rage of small children. Thus, for example, there is also the popular tactic of repeating some stupid, meaningless phrase a billion times" Arms for hostages, arms for hostages, arms for hostages, it's just about sex, just about sex, just about sex, dumb,dumb, money in politics,money in politics, Enron, Enron, Enron. Nothing repeated with mind-numbing frequency in all major news outlets will not be believed by some members of the populace. It is the permanence of evil; you can't stop it." (Ann Coulter) |
#25
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Wed, 17 Jul 2013 23:17:25 -0700, Gunner Asch
wrote: On Wed, 17 Jul 2013 14:27:18 -0400, Bob S wrote: On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob 3/4hp? I thought they were 1/3 hp? Reviewing the data..they are 1/2 hp Running a belt and in the airstream, check. Thats good. No cap? Not very many single phase motors of that size, dont have start/run caps. Sure there arent any inclosed in the fan housing somewhere? http://www.capacitorformotor.com/start_cap.html As for no lube points...I think Id pull down a motor and check. Some indeed are "permanantly lubricated" on the name plate. But I think Id look for either plugs in the end bearing covers or little holes that you can spritz oil into the bearings. Id also take a volt meter and put it on the fan circuit (s) somewhere and check your voltage on both the line and on the input to each fan occasionally. You said that there were several that were running slow...thats either a sign of bearings about to freeze up, shorted windings, low voltage at the motor...or bad run caps or even bad start caps on some..some motors. Get some measurements and you might determine whats going on. Gunner -- ""Almost all liberal behavioral tropes track the impotent rage of small children. Thus, for example, there is also the popular tactic of repeating some stupid, meaningless phrase a billion times" Arms for hostages, arms for hostages, arms for hostages, it's just about sex, just about sex, just about sex, dumb,dumb, money in politics,money in politics, Enron, Enron, Enron. Nothing repeated with mind-numbing frequency in all major news outlets will not be believed by some members of the populace. It is the permanence of evil; you can't stop it." (Ann Coulter) |
#26
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Thu, 18 Jul 2013 10:11:28 +1000, John G wrote:
Bob S laid this down on his screen : On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob Bob, I dont think you have ever really told us how these motors fail. You seem to be saying that it might be bearing failure. Then all the discussion about current, voltage etc is wasted. Motor bearings last for decades if rated and cooled correctly. Are yours cool? Is there an undue side load? eg belts too tight. Is the atmosphers corrosive? There are two different failure modes. One mode is that the motor is extremely rough-starting on low speed. It is rough enough to shake the greenhouse structure. It seems as though the torque is shifting rapidly from high to low and back again, which I take to mean that the starter circuit is cutting in and out, which in turn I take to mean that either the motor starter is defective or the motor does not have enough power to accelerate the fan. The other failure mode is that the motor runs unreasonably slowly. The motor may run at full speed when new, but before very long it gets slower and never runs at full speed again. The bearings do not seem to be seized up, they do not seem to have excessive friction, they do not make noises. Coolness is relative... The motors are not running hot enough to raise immediate blisters if I touch the casing, but I would not want to leave my hand pressed firmly against the casing for very long. Belt tightness: If I push on them they move inward a short distance. They are not loose enough to flap around and not tight enough to go "twang". They seem of ordinary tightness to me. I have no specification and no way of measuring it anyway. Corrosive atmosphere? Well, it is a greenhouse, there is a lot of moisture in the air, fertilizers and occasional insecticides are used. The fans are sold specifically for greenhouse use and the company is well-known and has been around for a long time, so I can only hope that they have designed with the environment in mind. Bob |
#27
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Wed, 17 Jul 2013 23:49:46 -0700, Gunner Asch wrote:
On Wed, 17 Jul 2013 23:17:25 -0700, Gunner Asch wrote: On Wed, 17 Jul 2013 14:27:18 -0400, Bob S wrote: On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob 3/4hp? I thought they were 1/3 hp? Reviewing the data..they are 1/2 hp Running a belt and in the airstream, check. Thats good. No cap? Not very many single phase motors of that size, dont have start/run caps. Sure there arent any inclosed in the fan housing somewhere? http://www.capacitorformotor.com/start_cap.html As for no lube points...I think Id pull down a motor and check. Some indeed are "permanantly lubricated" on the name plate. But I think Id look for either plugs in the end bearing covers or little holes that you can spritz oil into the bearings. Id also take a volt meter and put it on the fan circuit (s) somewhere and check your voltage on both the line and on the input to each fan occasionally. You said that there were several that were running slow...thats either a sign of bearings about to freeze up, shorted windings, low voltage at the motor...or bad run caps or even bad start caps on some..some motors. Get some measurements and you might determine whats going on. Gunner Right, 1/2 HP rating. I am wondering whether that is really enough to drive a 36 inch fan at the speed it is trying to go. The voltage seems to be fine, I have looked a couple times. The current is running right up to the nameplate rating, so there is certainly no spare capacity in the motor. Bob |
#28
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Thu, 18 Jul 2013 17:16:48 -0400, Bob S
wrote: On Wed, 17 Jul 2013 23:49:46 -0700, Gunner Asch wrote: On Wed, 17 Jul 2013 23:17:25 -0700, Gunner Asch wrote: On Wed, 17 Jul 2013 14:27:18 -0400, Bob S wrote: On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob 3/4hp? I thought they were 1/3 hp? Reviewing the data..they are 1/2 hp Running a belt and in the airstream, check. Thats good. No cap? Not very many single phase motors of that size, dont have start/run caps. Sure there arent any inclosed in the fan housing somewhere? http://www.capacitorformotor.com/start_cap.html As for no lube points...I think Id pull down a motor and check. Some indeed are "permanantly lubricated" on the name plate. But I think Id look for either plugs in the end bearing covers or little holes that you can spritz oil into the bearings. Id also take a volt meter and put it on the fan circuit (s) somewhere and check your voltage on both the line and on the input to each fan occasionally. You said that there were several that were running slow...thats either a sign of bearings about to freeze up, shorted windings, low voltage at the motor...or bad run caps or even bad start caps on some..some motors. Get some measurements and you might determine whats going on. Gunner Right, 1/2 HP rating. I am wondering whether that is really enough to drive a 36 inch fan at the speed it is trying to go. The voltage seems to be fine, I have looked a couple times. The current is running right up to the nameplate rating, so there is certainly no spare capacity in the motor. Bob Im going out on a limb here and saying the motor is too small or its geared too high. Probably geared too high would be my guess.. Ive put a lot of motors into machinery over the years..and a 1/2hp motor seems a bit small for a 36" fan run at "high speeds"...but its not part of my expertise. That being said..Ive got pedestal fans out in the shop that are spinning 36" fans out in the shop on 1/2 hp motors..but they are turning fairly slowly and are direct drive with no venturi effect. Mine are all about 1500 rpm if I recall correctely. Gunner -- ""Almost all liberal behavioral tropes track the impotent rage of small children. Thus, for example, there is also the popular tactic of repeating some stupid, meaningless phrase a billion times" Arms for hostages, arms for hostages, arms for hostages, it's just about sex, just about sex, just about sex, dumb,dumb, money in politics,money in politics, Enron, Enron, Enron. Nothing repeated with mind-numbing frequency in all major news outlets will not be believed by some members of the populace. It is the permanence of evil; you can't stop it." (Ann Coulter) |
#29
Posted to rec.crafts.metalworking
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greenhouse fan motors
Bob S brought next idea :
On Thu, 18 Jul 2013 10:11:28 +1000, John G wrote: Bob S laid this down on his screen : On Fri, 12 Jul 2013 22:48:27 -0700, Gunner Asch wrote: On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years That motor has Zero cooling. Notice..no internal or external fan on it? While it SHOULD provide its own cooling with the external fan...often times they dont cool very well because of the design of the center hub of the fan. The motor often times runs in a "dead air space" Id consider getting a different style motor with an external fan. As for the fan running slowly..that could be for several reasons. 1. Do you lubricate them properly and regularly? 2. Are the run caps going bad? 3. Is the start caps going bad? http://www.coleparmer.com/buy/category/motor-1-3-hp 4. Are the motors actually the right hp for the load? Would a 1/2hp motor be more appropriate? Gunner Thank you for the ideas. The motor is positioned above the fan hub, connected by a belt, and is actually in the air stream. Whether the cooling is adequate only the designer knows, but it is not obstructed at least. The motor name plate says that the motor bearings are permanently lubricated. Is suspect that the fan hub also uses permanently lubricated bearings, mostly because there were no lubrication instructions provided and there are no oiling points. The bearing housing for the fan hub is a good-sized chunk of hex stock open only at one end. The motor does not have an external "wart" for a capacitor. If there are any capacitors present then they are concealed inside the cylindrical housing somewhere. The motors are 3/4HP, which seems to be the size that this company suggests for a 36 inch fan. Bob Bob, I dont think you have ever really told us how these motors fail. You seem to be saying that it might be bearing failure. Then all the discussion about current, voltage etc is wasted. Motor bearings last for decades if rated and cooled correctly. Are yours cool? Is there an undue side load? eg belts too tight. Is the atmosphers corrosive? There are two different failure modes. One mode is that the motor is extremely rough-starting on low speed. It is rough enough to shake the greenhouse structure. It seems as though the torque is shifting rapidly from high to low and back again, which I take to mean that the starter circuit is cutting in and out, which in turn I take to mean that either the motor starter is defective or the motor does not have enough power to accelerate the fan. The other failure mode is that the motor runs unreasonably slowly. The motor may run at full speed when new, but before very long it gets slower and never runs at full speed again. The bearings do not seem to be seized up, they do not seem to have excessive friction, they do not make noises. Coolness is relative... The motors are not running hot enough to raise immediate blisters if I touch the casing, but I would not want to leave my hand pressed firmly against the casing for very long. Belt tightness: If I push on them they move inward a short distance. They are not loose enough to flap around and not tight enough to go "twang". They seem of ordinary tightness to me. I have no specification and no way of measuring it anyway. Corrosive atmosphere? Well, it is a greenhouse, there is a lot of moisture in the air, fertilizers and occasional insecticides are used. The fans are sold specifically for greenhouse use and the company is well-known and has been around for a long time, so I can only hope that they have designed with the environment in mind. Bob What does the Company say? He should have better knowledge than we can. Have you tried running with the belt off? That should give you an idea if they are overloaded. Do the pulleys increase the speed or decrease it at the fan? IE what's the ratio? You should be able to get the expected temp rise from the motor specs. Progressive failure as you describe sounds very strange. There really should be some failure to observe and fix. -- John G |
#31
Posted to rec.crafts.metalworking
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greenhouse fan motors
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#32
Posted to rec.crafts.metalworking
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greenhouse fan motors
Well, there is some good news. The company is going to send
replacement motors at 3/4 HP rather than 1/2 HP. If it is a simple overloading issue then maybe that will solve it. Bob On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years |
#33
Posted to rec.crafts.metalworking
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greenhouse fan motors
They sent three new motors, rated at 3/4 HP rather than the original
1/2 HP. They are physically more impressive. They have the same diameter as the original motors, but they are 9 1/2 inches long rather than 7 1/2 inches long. They also have an external capacitor cover; the original motors presumably have the capacitor within the motor housing, so the actual motor part is not as long as it looks. The new motors are rated at 12 A rather than 7A. I opened the first box and pulled out the motor, and the shaft was frozen so it wouldn't even turn. I know that some of you have good results with these guys, but I have serious doubts about their QC. The other two motors are installed and running, at least for the first few days... Thanks for all the ideas. Bob On Mon, 22 Jul 2013 16:46:12 -0400, Bob S wrote: Well, there is some good news. The company is going to send replacement motors at 3/4 HP rather than 1/2 HP. If it is a simple overloading issue then maybe that will solve it. Bob On Wed, 10 Jul 2013 14:14:03 -0400, Bob S wrote: I have a greenhouse with three fans from "American CoolAir". The problem is that the motors keep failing. At the moment two are running ridiculously slowly when powered on high speed. The other will start and run on high speed, but bangs on startup at low speed; it is as though the starter is kicking in and out. The company keeps sending replacements, but I would rather have motors that didn't need replacing. Is it possible to get drop-in replacement motors that would actually work more-or-less forever? The environment is not the greatest, with humid air blowing over them in summer and the motors in cold air and being frozen in winter, but I have had other appliances in similar conditions that never suffered a motor failure. The motor name labels say Emerson Model S63ZZJKW-7333 HP 1/2 RPM 1725/1140 SF 1.3 V 115 Hz 60 PH 1 Code L A 7.2 SFA 9.5 AMB 40C Made in Mexico It looks just like the one in this pictu http://www.federalindustrialsales.co...ph/m1-318.html I have been through about 7 motors in the past couple years |
#34
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greenhouse fan motors
On Sat, 17 Aug 2013 17:33:57 -0400, Bob S
wrote: I opened the first box and pulled out the motor, and the shaft was frozen so it wouldn't even turn. I know that some of you have good results with these guys, but I have serious doubts about their QC. Pull off that cover on the ass end and see if the fan is hanging up on the tail end of the cover. Ive had a few recently where the handling left something to be desired where they evidently dropped the motors on the fan housing and bent the sheet metal. I hammered the sheet metal back in place and they ran fine -- ""Almost all liberal behavioral tropes track the impotent rage of small children. Thus, for example, there is also the popular tactic of repeating some stupid, meaningless phrase a billion times" Arms for hostages, arms for hostages, arms for hostages, it's just about sex, just about sex, just about sex, dumb,dumb, money in politics,money in politics, Enron, Enron, Enron. Nothing repeated with mind-numbing frequency in all major news outlets will not be believed by some members of the populace. It is the permanence of evil; you can't stop it." (Ann Coulter) |
#35
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Sat, 17 Aug 2013 19:22:03 -0700, Gunner Asch
wrote: On Sat, 17 Aug 2013 17:33:57 -0400, Bob S wrote: I opened the first box and pulled out the motor, and the shaft was frozen so it wouldn't even turn. I know that some of you have good results with these guys, but I have serious doubts about their QC. Pull off that cover on the ass end and see if the fan is hanging up on the tail end of the cover. Ive had a few recently where the handling left something to be desired where they evidently dropped the motors on the fan housing and bent the sheet metal. I hammered the sheet metal back in place and they ran fine And I've had one where the fan was pressed on too far and rubbing on the front housing. Eyes open, guys! QC ain't what is used to be. Any more, "ISO 9001" means 'Someone filled out the right paperwork.' They can still build 'em wrong, pack 'em wrong, send 'em to the wrong address, etc. sigh -- Truth loves to go naked. --Dr. Thomas Fuller, Gnomologia, 1732 |
#36
Posted to rec.crafts.metalworking
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greenhouse fan motors
On Sat, 17 Aug 2013 20:57:32 -0700, Larry Jaques
wrote: On Sat, 17 Aug 2013 19:22:03 -0700, Gunner Asch wrote: On Sat, 17 Aug 2013 17:33:57 -0400, Bob S wrote: I opened the first box and pulled out the motor, and the shaft was frozen so it wouldn't even turn. I know that some of you have good results with these guys, but I have serious doubts about their QC. Pull off that cover on the ass end and see if the fan is hanging up on the tail end of the cover. Ive had a few recently where the handling left something to be desired where they evidently dropped the motors on the fan housing and bent the sheet metal. I hammered the sheet metal back in place and they ran fine And I've had one where the fan was pressed on too far and rubbing on the front housing. Eyes open, guys! QC ain't what is used to be. Any more, "ISO 9001" means 'Someone filled out the right paperwork.' They can still build 'em wrong, pack 'em wrong, send 'em to the wrong address, etc. sigh ISO 9000 just means you are getting the best documented junk you can buy. |
#37
Posted to rec.crafts.metalworking
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greenhouse fan motors
I would look into incorrect application.
If the atmosphere has excessive humidity, salt dust, and such, perhaps the OP needs to buy totally enclosed hostile duty motors. Also, possibly, motors are undersized for the fans that they are turning, and are overloaded. i |
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