PID just burned up

The PID on my Master Caster just bit the dust. I flipped the ON switch and was waiting for it to warm up and in about 3 minutes I heard a strange noise like paper rustling. It made this noise twice and then I saw lots of smoke coming out of the PID.
I removed the cover to discover the wire from the power supply cord had burned up at the connector block. The wire from the connector block to the switch also has a burned place on it, although it is not burned completely in two.
It appears the power supply cord is undersized at 18ga whereas the wire to the switch is 12ga. The cord from the MC to the PID is a 14ga cord so I'm sure that is a big NO NO. I did not build this PID, it came with the MC that I bought used. I have used it a good bit in the year that I have owned it.
Where can I find a 3 prong power that is a heavier gauge and also connector that goes to the connecting block?Attachment 204699

Attachment 204700
Attachment 204701
Attachment 204702

try https://www.grainger.com/product/POW...Code=P2IDP2PCP

If you don't have anything to scrounge one off of? getting a short heavy duty extension cord at a box store will probably be cheaper than Graingers. Or look to goodwill or other thrift store, for a cheap item with a good heavy duty cord.

I'm trying to source a heavier cord that connects to a C20 male connector in the back of the PID, plus a new C20 male connector. I think I have located a connector at Auber. I have several spare cords that I could splice but I wanted to keep the computer type plug in cord.

I found a 14ga cord and C20 male connector on Amazon that should work.

Quote:

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Originally Posted by JonB_in_Glencoe

If you don't have anything to scrounge one off of? getting a short heavy duty extension cord at a box store will probably be cheaper than Graingers. Or look to goodwill or other thrift store, for a cheap item with a good heavy duty cord.

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Heh, I have a heavy duty extension cord that I accidently nicked with a chain saw, now I use it for spare wire when needed and just clipped the damaged part off. Glad to see I'm not the only one.

I ran over a 12 ga x 100 ft cord with my lawnmower. I thought it would lay flat enough in the grass :( sometimes us guys over think things, most women would have moved it.

I'd get a 12 or 14 ga cord and crimp the eyes on it, remove the c20 connector and attach the cord to the box with something like this. (every connection reduces current and increases heat)

http://i.imgur.com/7rYmavA.jpg

You can use some of the remaining wire to fix the burnt wires.

I would be a little concerned as to why it burnt after this long. If you can, I would take the cover of the master caster visually inspect for any possible causes.

I think it was the undersized power cord and connector. The connector in the PID was only a 10 amp and the supply cord was 18 ga. The Master Caster has a 14 ga. cord and should not be plugged into a smaller cord from what I have always been told.

I would buy a short 12 gauge cord from one of the building material stores and cut it to fit. Or you can buy "SO" or "SOJ" cord by the ft at most wholesale electrical supply houses and put a male and female end on it. The short extension cord would be much cheaper. It looks like your terminal block got burned too so I would get another one. Once burned, you never get as good of a connection as before it was damaged.

Your Master Caster should have a name plate on it somewhere with the electrical data on it. Check the amp or watt rating.

The master caster pulls less then 15 amps at 120v
I know this because it plugs into a standard outlet.
At 220v it pulls less then 9 amp. I know this because I own one and measured it.

18ga wire can handle 16 amps.
The problem looks like a loose connection caused the wires to heat up.

Either way, go to homedepot or lowes and get a spool of 14 ga multi strand wire and you will be fine.

Change the terminal strip while your at it.

Quote:

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Originally Posted by HATCH

The master caster pulls less then 15 amps at 120v
I know this because it plugs into a standard outlet.
At 220v it pulls less then 9 amp. I know this because I own one and measured it.

18ga wire can handle 16 amps.
The problem looks like a loose connection caused the wires to heat up.

Either way, go to homedepot or lowes and get a spool of 14 ga multi strand wire and you will be fine.

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I agree about the loose connection.
But, I would discourage using 18 AWG wire.
I realize different authorities will spec different numbers, and even with the same authorities, they will update those numbers from time to time.
>>> At present time, UL specs 10 amps for a 18 AWG three conductor cord.
see link:
https://www.stayonline.com/reference...-ampacity.aspx

I've build industrial control panels to UL spec since 1993, I was the UL liaison in the many shops I've worked at, I know the UL-508A manual better than most.

I agree on the wire size. Stranded wire is suppose to carry more amps than solid, or so I have read in the past. But 12ga is for 20 amps, 14 for 15 amps, so I can't see 18 for more than 10amps. Since the Master Caster has a 14ga cord on it, that should be big enough. There didn't appear to be a loose connection anywhere. I could barely get the screw out of the connecting block where the burned into wire was. Maybe the connection in the crimp on wire terminal was a bit loose and it was covered with heat shrink tubing.
Anyway, thanks for all the tips. I have a c20 socket and 14ga cord on the way. I'll keep a watch on it and if that still doesn't work I can just straight wire it to the switch. I have a clamp on ammeter so I can check the amperage.

If the MC still has the factory heating element then my figures above will be right.
120 - 15 max
220 - 10 max

I bought it used from a member here, but as far as I know, it is original, not counting the conversion to air assist.

Possibly the crimp on connector was loose and created a high resistance.
After you crimp on the new connectors onto the new cable,
it would be a good idea to also solder the already-crimped connectors to insure good conduction and low resistance.

I'm with Hatch, i feel the issue was a loose connector, if there is any point of higher resistance, it will heat up till it burns the wire like this.

I'm back in business. My cord and connector came in today. The old socket connector was a 10a and the new one is rated at 20a. The new cord is 14ga and rated at 15a. So I cut a piece of spare SJ00 12ga cord and crimped on new ring connectors and female push on connectors. I feel much better with the heavier wire.
I plugged in the MC to the PID and turned it on. Apparently there was no damage to any of the other components as it came right on and started heating. I clamped on my meter and it is pulling 10.87-11.0 amps.
For anyone that has a PID, I would suggest taking off the top and checking the connections and also the size of the interior wiring.

Glad it's up and running again.

Good idea about checking the connections, look for any signs that the connections have gotten hot, different colour, melted plastic on the connectors.