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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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Hi,
I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks |
#2
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On 5/25/2018 10:40 AM, Dave, I can't do that wrote:
Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks Â* I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . Mine has a 4 wire socket , with 2 hots a neutral and a ground . I suggest you look up your model generator on the interwebs and see what the owners manual says . Out of curiosity , what's the motor do ? Just sit there and run or does it power something ? -- Snag Ain't no dollar sign on peace of mind - Zac Brown |
#3
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On Friday, May 25, 2018 at 9:32:00 AM UTC-7, Terry Coombs wrote:
Â* I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . Thanks Terry, It is only a 3-hole twist-lock socket on the generator. Looks like I will have to crank it up and get the meter out. I seem to recall using it to power something 220/240v about 6-years back, but no idea what wiring I used. |
#4
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Dave, I can't do that wrote:
On Friday, May 25, 2018 at 9:32:00 AM UTC-7, Terry Coombs wrote: I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . Thanks Terry, It is only a 3-hole twist-lock socket on the generator. Looks like I will have to crank it up and get the meter out. I seem to recall using it to power something 220/240v about 6-years back, but no idea what wiring I used. Three wires is a common generator output. You will find that you have 110 - 0 - 110 volts. Just the same that feeds into a breaker box. The fourth wire that you need is ground. On 99.9% of generators you will find a ground lug on the generator head or near the output panel. That goes to a good ground. -- Steve W. |
#5
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"Steve W." wrote in message
news ![]() Dave, I can't do that wrote: On Friday, May 25, 2018 at 9:32:00 AM UTC-7, Terry Coombs wrote: I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . Thanks Terry, It is only a 3-hole twist-lock socket on the generator. Looks like I will have to crank it up and get the meter out. I seem to recall using it to power something 220/240v about 6-years back, but no idea what wiring I used. Three wires is a common generator output. You will find that you have 110 - 0 - 110 volts. Just the same that feeds into a breaker box. The fourth wire that you need is ground. On 99.9% of generators you will find a ground lug on the generator head or near the output panel. That goes to a good ground. -- Steve W. Generator grounding isn't obvious because it interacts with other considerations, for instance checking for buried utility lines before driving a ground rod, or impenetrable frozen soil. https://www.osha.gov/OshDoc/data_Hur...generator.html Neutral is the power return conductor. Ground is for safety, only carries fault current, and is connected (bonded) to Neutral only at the main breaker box, or the generator frame when it is an isolated, "separately derived" power source. http://www.arrl.org/files/file/Techn...3-05%20(1).pdf "In other words, a ground rod is not required and, in fact, may create a hazard." Naval standards don't ground the neutral so that a single short won't take down the ship's power. The problem with grid power is that the pole transformer secondary could short to the 19.9KV distribution line and bring high voltage into your house if you didn't have a ground rod connected to the neutral. That isn't an issue for generators. |
#6
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On Fri, 25 May 2018 11:31:59 -0500, Terry Coombs
wrote: * I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . The 3 conductor 240 volt cable is 2 hots and ground. No neutral and thus no 120 volts. Mine has a 4 wire socket , with 2 hots a neutral and a ground . That's what it takes to have a neutral and a safety ground. John John DeArmond http://www.neon-john.com http://www.tnduction.com Tellico Plains, Occupied TN See website for email address |
#7
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On Sat, 26 May 2018 19:58:13 -0400, Neon John wrote:
On Fri, 25 May 2018 11:31:59 -0500, Terry Coombs wrote: * I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . The 3 conductor 240 volt cable is 2 hots and ground. No neutral and thus no 120 volts. Mine has a 4 wire socket , with 2 hots a neutral and a ground . That's what it takes to have a neutral and a safety ground. I think the NEC demands those only in hospitals. Everyone else has 2 hots and a not. (safety ground w/ no current) -- If we can ever make red tape nutritional, we can feed the world. --Robert Schaeberle |
#8
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On Sun, 27 May 2018 22:24:04 -0700, Larry Jaques
wrote: On Sat, 26 May 2018 19:58:13 -0400, Neon John wrote: On Fri, 25 May 2018 11:31:59 -0500, Terry Coombs wrote: * I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . The 3 conductor 240 volt cable is 2 hots and ground. No neutral and thus no 120 volts. Mine has a 4 wire socket , with 2 hots a neutral and a ground . That's what it takes to have a neutral and a safety ground. I think the NEC demands those only in hospitals. Everyone else has 2 hots and a not. (safety ground w/ no current) Required for ranges and driers for at least the last 10 years here in Canada - don't know abiout the backwaters of the USA |
#9
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On Mon, 28 May 2018 11:28:19 -0400, Clare Snyder
wrote: On Sun, 27 May 2018 22:24:04 -0700, Larry Jaques wrote: On Sat, 26 May 2018 19:58:13 -0400, Neon John wrote: On Fri, 25 May 2018 11:31:59 -0500, Terry Coombs wrote: * I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . The 3 conductor 240 volt cable is 2 hots and ground. No neutral and thus no 120 volts. Mine has a 4 wire socket , with 2 hots a neutral and a ground . That's what it takes to have a neutral and a safety ground. I think the NEC demands those only in hospitals. Everyone else has 2 hots and a not. (safety ground w/ no current) Required for ranges and driers for at least the last 10 years here in Canada - don't know abiout the backwaters of the USA New construction/retrofits must have that safety ground and the neutral, bonded inside the breaker box. Some locales are stricter than others about what a "retrofit" is. Most...most "backwaters" have it on the books..but really dont care. as long as its safe. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
#10
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On Mon, 28 May 2018 11:28:19 -0400, Clare Snyder
wrote: On Sun, 27 May 2018 22:24:04 -0700, Larry Jaques wrote: On Sat, 26 May 2018 19:58:13 -0400, Neon John wrote: On Fri, 25 May 2018 11:31:59 -0500, Terry Coombs wrote: * I think you'll find that those 3 pins are neutral and 220 on the other 2 , with either hot to the neutral at 110 . The 3 conductor 240 volt cable is 2 hots and ground. No neutral and thus no 120 volts. Mine has a 4 wire socket , with 2 hots a neutral and a ground . That's what it takes to have a neutral and a safety ground. I think the NEC demands those only in hospitals. Everyone else has 2 hots and a not. (safety ground w/ no current) Required for ranges and driers for at least the last 10 years here in Canada - don't know abiout the backwaters of the USA "Whatever for?" he queried, from said backwater. -- If we can ever make red tape nutritional, we can feed the world. --Robert Schaeberle |
#11
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On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that"
wrote: Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless it is tied to the generator ground and the generator is grounded. I'm betting that one wire is ground and that neither of the other two wires are tied to ground, meaning that there is no neutral wire on the 240 volt output. So you really need to get out the meter and see what the 240 out really is. Eric |
#12
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On Fri, 25 May 2018 17:38:09 -0700, etpm wrote:
On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that" wrote: I have a 1-1/2HP, 220v motor running from the dryer socket, all good. .... The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. .... The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless [...] "The reason neutral wires are called that is because they are tied to ground" seems to me to be incorrect. True, in US wiring, neutral wires usually have near-ground voltages on them, but more generally a neutral wire is one with no current flowing in it when a system is in balance. -- jiw |
#13
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On Sat, 26 May 2018 05:41:56 -0000 (UTC), James Waldby
wrote: On Fri, 25 May 2018 17:38:09 -0700, etpm wrote: On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that" wrote: I have a 1-1/2HP, 220v motor running from the dryer socket, all good. ... The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. ... The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless [...] "The reason neutral wires are called that is because they are tied to ground" seems to me to be incorrect. True, in US wiring, neutral wires usually have near-ground voltages on them, but more generally a neutral wire is one with no current flowing in it when a system is in balance. In US wiring the neutral does have current running through it. Eric |
#14
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#15
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"Terry Coombs" wrote in message
news ![]() On 5/26/2018 11:53 AM, wrote: On Sat, 26 May 2018 05:41:56 -0000 (UTC), James Waldby wrote: On Fri, 25 May 2018 17:38:09 -0700, etpm wrote: On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that" wrote: I have a 1-1/2HP, 220v motor running from the dryer socket, all good. ... The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. ... The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless [...] "The reason neutral wires are called that is because they are tied to ground" seems to me to be incorrect. True, in US wiring, neutral wires usually have near-ground voltages on them, but more generally a neutral wire is one with no current flowing in it when a system is in balance. In US wiring the neutral CAN have current running through it. Eric In a properly balanced load center that current will be minimized ... so I corrected your statement . -- Snag The neutral carries the difference between the hot leg currents. If the load current is 100A on one leg and 0A on the other the neutral will carry 100A. Increasing the load on the other leg decreases the current in the neutral, so with 100A through both hot legs the neutral carries 0A, not 200A, and it can be the same size cable as the two hots. Conceptually you get the right answer if you treat both loops of the circuit as separate and then add the currents, If the neutral has 100A flowing in from one hot leg and simultaneously 100A out to the other they will sum to 0 The relevant circuit analysis principle is that the currents into and out of a wire junction have to sum to zero, since you can't create or destroy electrons. A capacitor at the junction doesn't negate this rule, it turns the solution into a problem in differential calculus whose answer is an equation of voltage versus time. The Romans used the same net-sum principle to run an empire-wide checking system. When a merchant wrote a check for a cargo of wheat in Egypt the amount was simply deducted from tax payments sent back to Rome, and when he returned home the merchant had to reimburse the treasury (or become lion poop). Thus only the heavily guarded tax shipments were at risk from storms or pirates. -jsw |
#16
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On Sat, 26 May 2018 12:11:44 -0500, Terry Coombs
wrote: On 5/26/2018 11:53 AM, wrote: On Sat, 26 May 2018 05:41:56 -0000 (UTC), James Waldby wrote: On Fri, 25 May 2018 17:38:09 -0700, etpm wrote: On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that" wrote: I have a 1-1/2HP, 220v motor running from the dryer socket, all good. ... The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. ... The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless [...] "The reason neutral wires are called that is because they are tied to ground" seems to me to be incorrect. True, in US wiring, neutral wires usually have near-ground voltages on them, but more generally a neutral wire is one with no current flowing in it when a system is in balance. In US wiring the neutral CAN have current running through it. Eric * In a properly balanced load center that current will be minimized ... so I corrected your statement . Greetings Terry, Maybe you can educate me a little. After reading posts in reply to my post I got out the amp clamp and measured the current on both wires of the 125 volt receptacles in my shop. Plugging in a motor and turning it on the meter shows the same current draw on both the neutral and hot wires.In this case approximately 2.8 amps. I wired my shop with wire ways so it is easy to make measurements as the wire way covers come off easily and the wires just lay in the wire way. All the 125 volt receptacles on one wall are fed from the same breaker, on another wall another breaker, and so on. I did balance the load in the breaker panel so that two walls are fed from one leg of the 250 volt supply and two walls from the the other leg. I don't understand how the neutral can be balanced and show less current than the hot except at the breaker panel where the power comes in. What am I missing? What don't I understand? I did wire the shop myself but I was helped by a licensed electrician, the electrical code book, and the wiring was inspected and bought off by a particularly picky inspector. Thanks, Eric |
#17
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wrote in message
... On Sat, 26 May 2018 05:41:56 -0000 (UTC), James Waldby wrote: On Fri, 25 May 2018 17:38:09 -0700, etpm wrote: On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that" wrote: I have a 1-1/2HP, 220v motor running from the dryer socket, all good. ... The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. ... The reason neutral wires are called that is because they are tied to ground in the breaker panel which means there is no potential voltage between the neutral wire and the ground wire, at least in the breaker panel. So there is no neutral on the generator unless [...] "The reason neutral wires are called that is because they are tied to ground" seems to me to be incorrect. True, in US wiring, neutral wires usually have near-ground voltages on them, but more generally a neutral wire is one with no current flowing in it when a system is in balance. In US wiring the neutral does have current running through it. Eric The neutral is the center tap of the pole transformer, and the return for 120V loads. If you pull 50A from one hot leg and 40A from the other, the 10A difference will flow back on the neutral. A voltmeter tells you nothing about currents, you need a clamp-on ammeter to measure them. |
#18
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#20
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On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that"
wrote: Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks If your gen ouit is 240, nor 120/240, the motor will connect across the 2 "line out" terminals while the third terminal will be a ground - no neutral. If it is 120/240 it will have 4 wires unless it is ANCIENT |
#21
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On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that"
wrote: Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. Oh, no. Don't ask someone else. If you're going to wire it yourself, discover it yourself. It'll be in the manual, too. I got some of these from Ebay for my solar setup. Manual Transfer Switches, aka ORred circuit breakers. They run from 3A to 63A. https://is.gd/zddRgx You have to physically turn one off before the other will engage. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. No, it's much more likely to have phase lines (120vac) plus a ground for the genset. US 240vac has no neutral, only the 120vac does (line, neutral, and ground). How do I go about wiring that to run the motor? An ASCII diagram would be good. CAREFULLY. If in doubt, hire an electrician. Do the box install, switch install, and wire running yourself, and just have Sparky connect the wires to save money. Call them first to see if they will allow you to do that, though. Some want to do it all themselves. I saved $100 by doing my own wiring/outdoor breaker box for the A/C unit. Look at the genset diagram, look at the wiring from the socket, and follow the colors they use on your socket and extension cord. (black white green, black white bare, black red green, or black red bare usually. Green/bare is always ground.) I'd run the two phase wires from the output of the circuit breaker to the rotary or MT switch Input 1 terminals, run the two phase wires from the genset to the rotary MT switch Input 2 terminals. Then I'd run the existing wires (removed from the existing circuit breaker outputs) to the output terminals from the rotary or MT switch. Those wires go directly to the dryer socket on the wall. And run the ground from the genset to the circuit breaker panel ground bar. Be sure to cover the hot side of the switch, so fingers couldn't accidentally touch the hots. That hurts. Is your generator box outside, near the circuit breaker box, so you can drill a hole, put in a waterproof socket, and make a short extension cord from the genset to the house, where the switch will go? It makes things easier. I bought a 250' roll of 12/2 w/ ground Romex for outleted circuits and 100' of nice, flexible 12/3 wire for 240v bandsaw/DC/tablesaw and extension cord when I got this new-used house. There was no 240v in the (2-car) shop, so I put in 3 outlets, ran the wiring, and removed the 240v electric wallboard heaters, reusing the old circuit breakers for the shop. -- If we can ever make red tape nutritional, we can feed the world. --Robert Schaeberle |
#22
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On 5/25/2018 8:40 AM, Dave, I can't do that wrote:
Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks Break out your meter and find out. There are 3 pin twist lock 110V plugs. I have a few. |
#23
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On Wed, 30 May 2018 09:58:38 -0700, Bob La Londe
wrote: On 5/25/2018 8:40 AM, Dave, I can't do that wrote: Hi, I have a 1-1/2HP, 220v motor running from the dryer socket, all good. I was thinking of putting in a change over switch to run the motor from the generator when the power goes out as it does regularly out here. https://www.amazon.com/Baomain-Unive.../dp/B01IZ5ZFYC To save me dragging the gen-set out and starting it to find out what is coming out of the 240-socket, thought I'd ask here. The house wiring uses the 3-wire 110-0-110 for the 220/240 but the gen has three pins for the 240-out. I am guessing one is Ground and the others are Neutral and 240v. How do I go about wiring that to run the motor? An ASCII diagram would be good. Thanks Break out your meter and find out. There are 3 pin twist lock 110V plugs. I have a few. Virtually ALL gensets that use a 3 wire twist lock and claim to put out 240 volts...will have 240 across (2) of the connector pins and a ground. The odd shaped pin will be the ground. Least..its supposed to be. Period. Full stop End Program. Measure from 240 pin to ground. You may..may get 120 volts if the genset is worth a ****. I have several gensets..and they include a genset that claims to be 240..but isnt. Gunner --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
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