Couple of questions on RPC build

Here is a not great picture of the inside of the box. I can get a better picture later. IMG_20181105_120542799.jpg
 
The things you identify as a multiplier is likely a voltage divider generally comprised of resistors. You can use the existing meters if you know the resistance of the meters, current is usually given at full scale and labeled on the meter, in which case all you need to do is build a new divider network, however, your meter scale at full deflection is labeled "500" I have seen folks write their own scale and past over the old scale, and adjust the divider network accordingly. But they always look a bit cheesy, and new meters are relatively cheap. Frankly, I would scrap the meters or give to someone who can use them, and proceed building your RPC without them.
Yes, they appear to have 4 resistors in them, wired in series. And I don't plan on using them right now, they may end up on eBay to offset the cost of the box I am using in my build.
 
Just had a few minutes to check. 2017 NEC Article 240.4 (D) permits 14 AWG, so 14 AWG is correct. Also, 430.22 (G) explicitly permits 14 AWG. Do you have another cite in the NEC that says something else?
Back in the late 90's I was contractor on a remodel job, there was a 14 gauge branch circuit I wanted to use for a ½ hp fan motor, The electrician said it couldn't be done, it had to be a minimum 12 gauge for more than a ¼ hp motor. We changed it. I even asked the inspector if it was necessary (just to keep sparky honest) he said yes. Perhaps the code changed since then but it seems prudent to use a slightly heavier gauge anyway.
 
Hi Barncat,

I suspect that they are ammeters ! Need a close up of the front.

If they are, then they are probably moving iron type and would be very useful in monitoring the phase currents.
 
Yes, they appear to have 4 resistors in them, wired in series. And I don't plan on using them right now, they may end up on eBay to offset the cost of the box I am using in my build.

That particular meter panel seems to be an oddity even for a 3 phase 440 V system. Having three lights to indicate the presence of all three phase voltages is useful, but I don't know why you would also need to see all three phase voltages. Typically all one sees out there are perhaps three lights at the source and a single "power available" light at the equipment.
 
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