Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
|
|||
|
|||
Weller WTCP-N problem: No Heat
My weller soldering station failed yesterday for the first time in
years. I am not getting any heat. I would get the heater is out but is there a way to confirm what the problem is so I can try and track down some parts. Looking at the soldering pencil apart on my desk, which part is the heater and which part is the temperautre switch? I am guessing that the barrel is the heater element but I am really not sure. Take Care all. |
#2
|
|||
|
|||
"Ian" wrote in message om... My weller soldering station failed yesterday for the first time in years. I am not getting any heat. I would get the heater is out but is there a way to confirm what the problem is so I can try and track down some parts. Looking at the soldering pencil apart on my desk, which part is the heater and which part is the temperautre switch? I am guessing that the barrel is the heater element but I am really not sure. Take Care all. The N model should be similar to my WTCPS, which appears to be essentially the same as the new WTCPT on the Weller site. To get the exploded diagram of the WTCPT, go to http://www.cooperhandtools.com/brands/weller/index.cfm and search for "wtcp". Click the WTCPT station link and from the list select WTCPT_OI_PL.pdf |
#3
|
|||
|
|||
I have a Weller solder iron and has similar problem end up with bad surface
mount electrolytic capacitors. Good luck Eric "Ian" wrote in message om... My weller soldering station failed yesterday for the first time in years. I am not getting any heat. I would get the heater is out but is there a way to confirm what the problem is so I can try and track down some parts. Looking at the soldering pencil apart on my desk, which part is the heater and which part is the temperautre switch? I am guessing that the barrel is the heater element but I am really not sure. Take Care all. |
#5
|
|||
|
|||
In article ,
Jim Adney wrote: On 16 Aug 2004 17:30:48 -0700 (Ian) wrote: My weller soldering station failed yesterday for the first time in years. I am not getting any heat. I would get the heater is out but is there a way to confirm what the problem is so I can try and track down some parts. Things to check: Make sure that you're getting 24VAC out of the base. Some of these have a fuse inside. Make sure there are no broken wires in the cord (very common.) Looking at the soldering pencil apart on my desk, which part is the heater and which part is the temperautre switch? I am guessing that the barrel is the heater element but I am really not sure. The heater is in the barrel, while the switch is back inside the handle. You should be able to figure out the source of the problem with an Ohmmeter. These are excellent units, well worth fixing. A common problem is that the contacts in the switch get oxidized. It's possible to take the switch apart and clean the contacts with very fine emery paper or crocus cloth. The operation of the temperature control is by means of the Curie effect. The heater switch is held closed by magnetism until the temperature reaches the set point (determined by the alloy that the tip insert is made from -- the number on the base multiplied by a hundred is the setpoint). At the set point, the tip insert becomes non-magnetic, and a spring pops the contacts open. When the tip cools down, the magnetism returns, and the switch is pulled closed again. Isaac |
#6
|
|||
|
|||
On Thu, 19 Aug 2004 07:35:42 GMT Isaac Wingfield
wrote: A common problem is that the contacts in the switch get oxidized. It's possible to take the switch apart and clean the contacts with very fine emery paper or crocus cloth. I'd recommend a very mild points file rather than an abrasive, because abrasive can get left behind, embedded in the contact material, and it's an insulator. Whatever you use, however, I agree that you need to be very careful not to be too aggressive. The operation of the temperature control is by means of the Curie effect. The heater switch is held closed by magnetism until the temperature reaches the set point (determined by the alloy that the tip insert is made from -- the number on the base multiplied by a hundred is the setpoint). At the set point, the tip insert becomes non-magnetic, and a spring pops the contacts open. When the tip cools down, the magnetism returns, and the switch is pulled closed again. Yes, exactly. A very cool system. ;-) - ----------------------------------------------- Jim Adney Madison, WI 53711 USA ----------------------------------------------- |
#7
|
|||
|
|||
|
#8
|
|||
|
|||
"tom_mc_h" wrote in message om... (Ian) wrote in message . com... My weller soldering station failed yesterday for the first time in years. I am not getting any heat. I would get the heater is out but is there a way to confirm what the problem is so I can try and track down some parts. Looking at the soldering pencil apart on my desk, which part is the heater and which part is the temperautre switch? I am guessing that the barrel is the heater element but I am really not sure. Take Care all. Usual fault is that the inside of the barrel has got rusty and the magnetostat is stuck or can't move. Take the sleeve off, remove the bit, and push a screwdriver into the tube and give the 'stat shaft a few good wellyings. Usually cures it great. Unless it is very old and decrepit it is unlikely to be the switch although it is not unknown. -- Woody |
#9
|
|||
|
|||
In article ,
Jim Adney wrote: On Thu, 19 Aug 2004 07:35:42 GMT Isaac Wingfield wrote: A common problem is that the contacts in the switch get oxidized. It's possible to take the switch apart and clean the contacts with very fine emery paper or crocus cloth. I'd recommend a very mild points file rather than an abrasive, because abrasive can get left behind, embedded in the contact material, and it's an insulator. Whatever you use, however, I agree that you need to be very careful not to be too aggressive. Crocus cloth is explicitly recommended for cleaning motor commutators, so it should be fine -- actually, it's *very* fine 8^} Some abrasives are insulators, and some are conductors; carborundum is a conductor, for example. If I need a bit more "aggression" than crocus cloth provides, I use a 600 grit carborundum "wet or dry" paper; the grit is very solidly attached. A file, even a fine one, will remove a lot more material than an abrasive. Isaac |
#10
|
|||
|
|||
On Sat, 21 Aug 2004 04:49:04 GMT Isaac Wingfield
wrote: Crocus cloth is explicitly recommended for cleaning motor commutators, so it should be fine -- actually, it's *very* fine 8^} Yes, I agree, it's very fine. As long as it doesn't leave anything behind it should be fine. Some abrasives are insulators, and some are conductors; carborundum is a conductor, for example. If I need a bit more "aggression" than crocus cloth provides, I use a 600 grit carborundum "wet or dry" paper; the grit is very solidly attached. A file, even a fine one, will remove a lot more material than an abrasive. I really don't think carborundum is a conductor. Can you find support for this statement anywhere? I agree about the file. A more proper tool would be a burnisher. Contact burnishers just look like a thin flexible steel leaf with a matte finish which is very slightly abrasive. They're sold for this purpose, but I don't know if you can still buy them anywhere. I hear they were fairly common in the old days when IBM accounting machines consisted of banks of relays which were actually expected to be serviced. - ----------------------------------------------- Jim Adney Madison, WI 53711 USA ----------------------------------------------- |
#11
|
|||
|
|||
In article ,
Jim Adney wrote: On Sat, 21 Aug 2004 04:49:04 GMT Isaac Wingfield wrote: Crocus cloth is explicitly recommended for cleaning motor commutators, so it should be fine -- actually, it's *very* fine 8^} Yes, I agree, it's very fine. As long as it doesn't leave anything behind it should be fine. Some abrasives are insulators, and some are conductors; carborundum is a conductor, for example. If I need a bit more "aggression" than crocus cloth provides, I use a 600 grit carborundum "wet or dry" paper; the grit is very solidly attached. A file, even a fine one, will remove a lot more material than an abrasive. I really don't think carborundum is a conductor. Can you find support for this statement anywhere? I was speaking from a memory of having used carborundum power resistors years ago in FM broadcast transmitters; they were small for their power rating because they could operate at a very high temperature without much resistance change. I found one mention of 1000 ohm-cm. at 1000 degrees C. Here's an interesting URL I ran across: http://home.luna.nl/~arjan-muil/radio/carborundum.html Isaac |
#12
|
|||
|
|||
On Sun, 22 Aug 2004 06:28:03 GMT Isaac Wingfield
wrote: I was speaking from a memory of having used carborundum power resistors years ago in FM broadcast transmitters; they were small for their power rating because they could operate at a very high temperature without much resistance change. Now that you mention it, we use carborundum power resistors quite a bit where I work. I probably have quite a few of them in my current project. I'm still not sure that this is something we'd want caught in our relay contacts, however. I'm not actually sure what serves as the resistive material in a carborundum resistor. Is it the carborundum itself? I found one mention of 1000 ohm-cm. at 1000 degrees C. Not quite what I had in mind for my relays either. At 1000 C, I suspect that many things become more conductive. Here's an interesting URL I ran across: http://home.luna.nl/~arjan-muil/radio/carborundum.html Thanks, I'll check it out. - ----------------------------------------------- Jim Adney Madison, WI 53711 USA ----------------------------------------------- |
#13
|
|||
|
|||
On Sun, 22 Aug 2004 21:33:24 -0500 Jim Adney
wrote: On Sun, 22 Aug 2004 06:28:03 GMT Isaac Wingfield wrote: I was speaking from a memory of having used carborundum power resistors years ago in FM broadcast transmitters; they were small for their power rating because they could operate at a very high temperature without much resistance change. I checked with some other people at work and they pointed out that SiC is actually a bit of a semiconductor, so it is somewhat conductive and that's why it can be made into a resistor. No one knew what the resistor people do to it to vary the resistivity, however. The semiconductor people are working with it to see if they can make power semis from SiC that will operate happily at 400 C. If they succeed, it will be a lot easier to "cool" something that is still happy at that temp. - ----------------------------------------------- Jim Adney Madison, WI 53711 USA ----------------------------------------------- |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Heat Keeps Shutting Off | Home Repair | |||
A/C & Heater Replacement?? | Home Repair | |||
A/C & Heater Replacement?? | Home Ownership | |||
turn-off: Texas heat pump sellers slow to give "happy-user" refs | Home Ownership | |||
heat exchanger calculations | UK diy |