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Noticed last week that when I unplugged my dust collector from the blast gate control to change bags that the control box seemed to come apart a bit. Today, I pulled the switch off the wall to check it out and noticed the odor. No mistaking that smell. Opened it up and sure enough..... :eek:
This is (was) a JDS 110v control. Way out of warranty. Any suggestions for a higher quality replacement?
Is this a simple 110v switch in a special box or something else? (Sorry, I can't help locating a replacement.)Quote:
Originally Posted by Brian Tymchak
However: I can't tell from the picture the extent of any internal damage but I usually don't let a little thing like burned contacts stop me. :) (I'm too cheap)
Unless the device was pulling way more current than it was rated for or something else failed, in my experience overheating at a connection is usually a result of a poor electrical connection resulting in some resistance. That resistance can cause heat which causes more resistance which causes more heat which.... The poor connection can come from corrosion from humidity or other environmental conditions, from a wire or connector which is not clean, or from not tightening the connector enough.
I first try disassembling the device to assess the internal damage. Sometimes the contacts can be cleaned up and a new section of wire exposed. Sometimes a new screw and piece of brass can be fabricated to replace the original connector. Sometimes I steal connectors from other electrical things. Sometimes it is easier to eliminate the pressure connector and make a good connection inside, perhaps by soldering. Where plastic parts are burned or corroded some reinforcement with some epoxy might stabilize things or just put everything in a new box.
BTW, when making any connection I've taken to putting a bit if dielectric grease on the parts. This keeps air and moisture away from the metal. (This is especially useful for connections on vehicles and farm equipment.)
JKJ
Looks like a loose or corroded connection and as a result the wire heated. Maybe cut the wire back and reconnect?
+1 - - I've seem similar damage when the wire 'clamp' tightens up on the insulation rather than the wire.Quote:
Originally Posted by Joe Jensen
Assuming controller still functions properly, de-term the damaged wire, cut it back to clean copper and good insulation, then strip to the recommended exposure (probably a strip gauge on the device). Pull the screw and cage clamp (if possible), then wire brush it as best you can. Put the screw back and re-terminate the wire - make sure its clamped metal-on-metal - and tug test.
Thanks guys! You all must be more comfortable working with electric than I am but you've convinced me to take another look at it.
This is the low voltage switch in an automated blast gate package that I bought over 10 years ago. I noticed today that this product is no longer for sale. The fried contact is on the plug that the DC plugs into.
wrt to cutting the wire back to good copper, I'll check that. It is pretty tight in there, not a lot of extra wire inside the box. Maybe I can just rewire it. I didn't look too deeply into fixing it after I saw the burnt wire.
John - I have a basement shop, nice and dry. I can think of no way moisture found its way to this switch. But I did get to thinking though. 3 weekends ago, I was in a pretty long session of planing Ash for my timberframe-inspired lumber rack. I ended up overfilling the collection bag once. I wonder if that or the extra long session somehow caused the DC to pull more current.
I do unplug the DC from this switch at the end of any day I use it (which at max is a couple times a week). Maybe over 10 years it just loosened up the contacts in the plug.
Appreciate the suggestions!
Thanks!
I've never been comfortable using the clamps on solid wire. Call it personal preference, but, to me, the clamps were designed for stranded wired and I've seen too many cases just like this one from trying to put solid wire in them. Bend a hook on the solid and put it under the screw. Lot less problems.Quote:
Originally Posted by Malcolm McLeod
The picture of the device in question clearly shows stranded wire.Quote:
Originally Posted by Brad Alexander
I’m normally all for cleaning it up and re connecting, but I’ve worked with electricity professionally for 30 years. My personal opinion is that, based on the advanced state of the damage coupled with the relative inexperience of the OP, it would be wiser to replace rather than repair.
The best way I know to make a connection with stranded wire is to crimp a terminal on the wire and clamp the terminal.
JKJ
i agree completely, assuming one uses the correct connector (properly rated for wire size AND voltage) and the corresponding approved tool. Using an automotive connector rated for 12v and squashing it on with a pair of needle nosed pliers is a recipe for heartburn.Quote:
Originally Posted by John K Jordan
The pro crimp tools can not be released until the crimp is tight smashed down to the thickness it is supposed to be. Same for pex clamp tools. Yes it can be released and reset but after few notches you are committed to completely squeezing the crimp.
Bill D
I finally bought a ratcheting crimper with changeable dies. My crimps are so much more secure and look so much more professional. I should have bought one years with all the controllers i have wired for cnc machines. Highly recommend one!
This looks like the problem--the push-in connections are for solid wire, not stranded. Terminate properly at the screw terminal.Quote:
Originally Posted by John Lanciani
I found a little extra time last week to dissect the switch. The burnt red wire runs to a soldered connection on a circuit board. The plastic plug case has quite a bit of internal damage where the brass contact and clamp screw sit. The supporting wall for the contact and screw was burnt and crumbled away when I opened the plug case. The wire, contact, and clamp screw were very damaged inside the case. But the nut on the clamp screw appeared to be fairly tight. If I had to guess the true cause of the failure, I would say that when the switch was assembled, they just missed getting the wire behind the nut on the screw. The other contact was solidly clamped.Quote:
Originally Posted by John Lanciani
So, as there is case damage and I don't have the soldering equipment to replace the wire, as John recommends, I will opt to replace the entire switch, if I can find a suitable replacement. At least I still have DC, just not automated gates.
Appreciate all the advice and info.
Thanks!