Todd Adornato Posted December 22, 2024 Posted December 22, 2024 Hi folks, I have a cream-colored GE 55X165 one-speed fan which doesn’t work. I pulled the stator and checked for resistance between the two head wires, and got an open load. There’s damage to the winding in one spot, where it looks like someone tried to force one of the cover bolts past the winding. Touching the multimeter’s probe to the exposed wiring produces a resistance reading. Is it even worth paying for a rewind considering the make and model? Overall the fan is in very good condition, so I’d like to try and save it but not if it’s going to cost more than the monetary value of the fan. Pics below. Thanks. Quote
Roger Borg Posted December 22, 2024 Posted December 22, 2024 If one break, you can scrape the tip of the the insulation, solder, and revarnish. If multiple breaks, figure out the main ends, disregard the few loops, and solder the two halves. Seems you have nothing to lose, and a possible easy fix. Good luck... 1 Quote
Todd Adornato Posted December 22, 2024 Author Posted December 22, 2024 (edited) Roger, thanks for the input. I used a magnifying glass to get a closer look, and it appears as if the previous owner tried to drive home the bolt with a hammer or something, as the damaged area looks like it received blunt force trauma. A bunch of the windings were forced together, but after picking most of them apart with a fine point, I couldn’t see any breaks. My question now is; can the wires being jammed together cause a short, even if there are no breaks in any of the wires? Here’s a pic - the damaged wires are along the lower portion of the winding. You might be able to see bright shiny spots along some of the wires. Edited December 22, 2024 by Todd Adornato Quote
Roger Borg Posted December 23, 2024 Posted December 23, 2024 4 hours ago, Todd Adornato said: Roger, thanks for the input. I used a magnifying glass to get a closer look, and it appears as if the previous owner tried to drive home the bolt with a hammer or something, as the damaged area looks like it received blunt force trauma. A bunch of the windings were forced together, but after picking most of them apart with a fine point, I couldn’t see any breaks. My question now is; can the wires being jammed together cause a short, even if there are no breaks in any of the wires? Here’s a pic - the damaged wires are along the lower portion of the winding. You might be able to see bright shiny spots along some of the wires. I would wait for confirmation from others, but if you have readings and continuity and no breaks, I suspect revarnishing it would be sufficient... Quote
Todd Adornato Posted December 23, 2024 Author Posted December 23, 2024 16 minutes ago, Roger Borg said: I would wait for confirmation from others, but if you have readings and continuity and no breaks, I suspect revarnishing it would be sufficient... No, the reading is still an open load. If I touch the probe to the damaged area, I get a reading on one lead but not the other. 1 Quote
Mark Olson Posted December 23, 2024 Posted December 23, 2024 Hi Todd, with a "bruise" that bad, even if you did manage to establish continuity, the windings would very likely have turn to turn shorts, which are difficult to detect. Turn to turn shorts always result in a burn out. Nobody can tell you what your fan is worth, but I can tell you that rewinding that motor costs relatively little. P.M. me about it if you wish. 1 4 Quote
Stan Adams Posted December 23, 2024 Posted December 23, 2024 Don't try to repair this, spraying varnish only helps if you have a scraped area, this one is toast. Listen to Mark, he does great work. 2 Quote
Tony Clayton Posted December 23, 2024 Posted December 23, 2024 I second what Stan said! Mark knows what he's doing. Great guy, quality craftsmanship. 1 Quote
Roger Borg Posted December 23, 2024 Posted December 23, 2024 16 hours ago, Mark Olson said: Hi Todd, with a "bruise" that bad, even if you did manage to establish continuity, the windings would very likely have turn to turn shorts, which are difficult to detect. Turn to turn shorts always result in a burn out. Nobody can tell you what your fan is worth, but I can tell you that rewinding that motor costs relatively little. P.M. me about it if you wish. Wouldn't a meggar be able to identify the integrity of the damaged windings? Quote
Mark Olson Posted December 24, 2024 Posted December 24, 2024 Hi Roger, yes, a megger will verify insulation integrity to ground, and where windings can be electrically disconnected and isolated from each other, but a megger can not indicate direct shorts within the same coil, unless the short also extends to ground, or another isolated winding.. 1 Quote
Roger Borg Posted December 24, 2024 Posted December 24, 2024 13 hours ago, Mark Olson said: Hi Roger, yes, a megger will verify insulation integrity to ground, and where windings can be electrically disconnected and isolated from each other, but a megger can not indicate direct shorts within the same coil, unless the short also extends to ground, or another isolated winding.. Hi Mark- To better my understanding, are you saying a meggar will only indicate if the windings short out to the motor body, and not winding to winding? And for example, if a 4 or 6 pole motor (ie not a basket weave), ideally you'd isolate each pole to test? And expanding, is a growler a better testing device in this scenario? Thanks, enjoy learning about the hows and whys. Happy holidays... Quote
Mark Olson Posted December 25, 2024 Posted December 25, 2024 7 hours ago, Roger Borg said: Hi Mark- To better my understanding, are you saying a meggar will only indicate if the windings short out to the motor body, and not winding to winding? Yes And for example, if a 4 or 6 pole motor (ie not a basket weave), ideally you'd isolate each pole to test? Larger three phase motors are tested this way And expanding, is a growler a better testing device in this scenario? A growler, the way I know it, is better for armature testing Thanks, enjoy learning about the hows and whys. Happy holidays... Quote
Roger Borg Posted December 26, 2024 Posted December 26, 2024 On 12/24/2024 at 8:09 PM, Mark Olson said: Hi Mark, thanks for the reply. Regarding magnet wires, wouldn't wires shorting internally by default short to ground, since the windings touch the stator which touch the metal body? How would they be insulated to ground? And independent of that question, what is the protocol to test for internally shorted wires (or degrading insulation) if not a meggar? Thanks... Quote
Mark Olson Posted December 27, 2024 Posted December 27, 2024 Picture in your mind two parallel wires touching where the insulation is broken. There is a short there. If the wires are only touching each other and not anything else, then a megger will not detect that. One may be able to detect the short with an ohm meter, but unless one knows exactly what the reading should be, then one could not possibly know that the turn to turn short existed. That is why I stated turn to turn shorts are very difficult to detect. Quote
Roger Borg Posted December 29, 2024 Posted December 29, 2024 On 12/27/2024 at 6:55 AM, Mark Olson said: Picture in your mind two parallel wires touching where the insulation is broken. There is a short there. If the wires are only touching each other and not anything else, then a megger will not detect that. One may be able to detect the short with an ohm meter, but unless one knows exactly what the reading should be, then one could not possibly know that the turn to turn short existed. That is why I stated turn to turn shorts are very difficult to detect. Ok, gotcha, thanks for the info. Hoping situations like this are few and far between. All the best... Quote
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