New Power Cord......

[Sarman47]

Happy New Year

I just replaced my power cord on a Westinghouse WB-126-6A-10 (she is a big girl) and now it is not working the same.

The old cords male end had the ground pin removed, although the ground wire was attached to the compressor deck. So I buy a 15 amp rated outdoor extension cord and cut the female end off. Attach electrical connectors and connect as old was set up.

Compressor works, cuts in and out. When I tried to vend it took coin and gave change. When I pushed the button to vend, nothing comes out and the vend motor keeps turning.

So the only thing different is the ground pin is connected and is plugged into the outlet.

Just wondering if any of the members on here have had this problem happen.

Thank You

Jeff

[Slapshot42]

Jeff,
 
Can you take a picture of your wiring, coin mechansim area, and vend motors?

I have some general troubleshoot advicd for a push button machine but need to see your set up...

[johnieG]

if you buy a grounding adapter & carefully plug the machine into the power outlet without grounding it, then test it again, IF it acts "normally" then you have some kind of a neutral to ground issue, but in any case you have a wiring issue, be careful in case the chassis could be hot.

[tkaz]

Easy and safer way to check if you have a neutral to ground issue is to use a multimeter on the replacement plug.  Put it on the continuity setting and touch the ground on the plug to the neutral and hot with the probes.  If you have continuity, you've got problems.

[johnieG]

Easy and safer way to check if you have a neutral to ground issue is to use a multimeter on the replacement plug.  Put it on the continuity setting and touch the ground on the plug to the neutral and hot with the probes.  If you have continuity, you've got problems.

True, a multi-meter (Ohms scale) would be the safe way to check, however it (the machine) has been running sans grounding pin on the power cord prior to him trying to splice a replacement onto the originals  cut-back "stub" ( I assume) unless he spliced the new cord into another area or the wiring harness or electrical terminal blocks.

[johnieG]

National electrical code states that the Neutral and the ground/earth are NOT the same thing on a 120 volt electrical circuit. they are NEVER bonded inside the machine, if they were, If the polarity gets reversed in such a machine with an open ground pin ( as he said it's missing on his original cord) yes, you'd get shocked on your A$$   

in any case, there is an electrical issue with the machine. check you wiring for brittle/dry rotted insulation on the wiring on or near the spot where you've connected your replacement cord.

[tkaz]

What about a mis-wired vending or inventory switch?  The normally open or closed circuits could have inadvertently been tied to ground causing the circuit not to reset after a vend cycle.  Maybe the reason the previous owner pulled the ground off?

[Sarman47]

Easy and safer way to check if you have a neutral to ground issue is to use a multimeter on the replacement plug.  Put it on the continuity setting and touch the ground on the plug to the neutral and hot with the probes.  If you have continuity, you've got problems.

I checked the old power cord ground pin wire with multimeter on continuity against the two wires and all was fine. Also checked the new wire, all was fine.

I have attached a picture of the old power cord wired into the machine and a picture of the new cord end.

Thanks for your help.

Jeff

[Sarman47]

Jeff,
 
Can you take a picture of your wiring, coin mechansim area, and vend motors?

I have some general troubleshoot advicd for a push button machine but need to see your set up...

Here is a picture of the coin mechanism area.

Thank You

Jeff

[Sarman47]

Neutral to ground issue? They are one in the same. If the chassis was hot it would have tripped the breaker the moment he plugged it in, if he bonded in the correct place.
The only purpose of the ground wire is to bond the metal chassis so that if it becomes energized it trips the breaker instead of using you as a path to ground.
Everything works, It's obvious the vend motor is working so it has both a hot and neutral.
Without seeing pictures, my guess would be you have a switch problem. Purely coincidence.

Yes. I am wondering if one of the relays is now bad ? When you say switch. Do you mean the relays on the front of the machine ? See attached picture.

Thanks for you're help.

Jeff

[Sarman47]

What about a mis-wired vending or inventory switch?  The normally open or closed circuits could have inadvertently been tied to ground causing the circuit not to reset after a vend cycle.  Maybe the reason the previous owner pulled the ground off?

I have reconnected the old power cord. And now there is nothing from the relays (use to buzz until you selected a drink) and the quarters now drop right threw the coin mechanism.

Thank you for the quick reply.

Jeff

[johnieG]

Yes I am, Plus ( Electronic field service engineer 30 years, Certified biomedical technician 10 years, electrical Journeyman 2 years out now, & just attended the 2014 code update class, lots of interesting changes in regards to grounded conductors vs ground electrodes) and I'm not trying to dive too deep into an esoteric discussion on the terms of neutral vs ground.

What I am saying folks is to be careful & work safe on these early machines, the vending circuits & controls and selection switches are using line voltage.

Yes the earlier circuit diagram posted was highlighted from another discussion, so I reposted it in gray scale.   Oh & watch out for that "magic smoke" it'll get you every time. 

[johnieG]

The coil pictured looks to be the credit relay, it's not unusual for them to look a little toasted, he'd have to lift the terminal connections off of it & ohm it out at this point. ( he said it was latched "On" all the time)  but even then it shouldn't cause a vend cycle until a selection is made, it could also be a stuck selection switch.

If the relay ohms OK, I'd reconnect it, power up the machine and observe if vend motor starts running right off the get-go ( without any coins being inserted), and the credit relay is being held in, then I'd pull the coinmechs Jones (power) connector & see if it ( the credit relay) unlatches & the vend motor stops spinning.  It is possible the coinmechs internal vend relay is stuck (and the MARS coinmech shown isn't known for its reliability.)  

some machines also used a delivery switch ( down by the bottle chute) that told the credit relay that the soda has "dropped" & it allows the relay to unlatch, terminating the vending cycle.

[Sarman47]

The coil pictured looks to be the credit relay, it's not unusual for them to look a little toasted, he'd have to lift the terminal connections off of it & ohm it out at this point. ( he said it was latched "On" all the time)  but even then it shouldn't cause a vend cycle until a selection is made, it could also be a stuck selection switch.

If the relay ohms OK, I'd reconnect it, power up the machine and observe if vend motor starts running right off the get-go ( without any coins being inserted), and the credit relay is being held in, then I'd pull the coinmechs Jones (power) connector & see if it ( the credit relay) unlatches & the vend motor stops spinning.  It is possible the coinmechs internal vend relay is stuck (and the MARS coinmech shown isn't known for its reliability.)  

some machines also used a delivery switch ( down by the bottle chute) that told the credit relay that the soda has "dropped" & it allows the relay to unlatch, terminating the vending cycle.

Hi JohnieG

Thank You for your trouble shooting advice.

I ohm out the relay, looks like it is dead. Ordered 2 new relays today. So while I wait on the relays I am going to go over all the wiring. Replace anything that is suspect (better safe then sorry). As well as check the coinmechs internals.

Jeff