Strand C21 Dimmer Rack phase problems

[jack0riley]

I just installed a C21 rack and the self-test says that phase c is 120v on 60hertz. Phases A and B are 60v on 60hertz. How do I bring down the voltage on phase c?

 

[MNicolai]

The real question is how do you bring up the voltage on the phases A and B

 

[mstaylor]

I assume you have a breaker panel or disconnect feeding the dimmers. You need to check that and xsee what voltages you have there. As Mike says, you need to bring the other two legs up. You next step may be an electrician or a call to the power company.

 

[Sony]

Yea....Phase C is the correct one... Phases A and B are the screwy ones, honestly you REALLY need to call a licensed electrician. The fact that you just installed a dimmer rack and don't even know what the proper voltage that needs to be feeding the rack is makes me worried. Seriously? You could kill someone, including yourself, electricity is not to be trifled with. Call a licensed Electrician!!!!!!!

 

[jack0riley]

No I already disconnected and checked the voltages. Everything's ok. It's just on the pretests that the readings are wrong.

 

[avkid]

So everything is working correctly, but the pretest numbers come up wrong?

 

[jack0riley]

Everything's working correctly except for the pretests. I'm guessing it's only the board that's not reading correctly. I just hope it's not gonna cause a problem later

 

[avkid]

Is this a new rack?

 

[jack0riley]

Yeah it's a new rack. And I had a show this weekend there was no dimming in the lights?? They only went full on or full off? It has to be a programming problem

 

[gafftaper]

Have you called Strand Tech Support?

 

[jack0riley]

I talked with a Strand sub-contractor yesterday. I gave him the rack's ip address. We'll see what he can do.

 

[phenry]

I would let an electrician or the Strand install tech handle this as it has to do with live voltage.
When the rack is installed, the actual voltage coming in needs to be measured and the phase trim adjusted accordingly so the correct output is displayed.
Your lights were not dimming? Did you have any that did dim? Usually a rack that is not diming correctly is an indication that 2 of the phases are swapped. I ask if you have any dimming because if you have 2 phases swapped and one correct, you will have one phase of dimming, 1 phase of non dim at some percentage, and one phase just non dim at about 1 percent. I will not leave instructions here, but please have you or the tech on site call me if you need help.

 

[65535]

If the rack thinks it's getting fed one proper 120V leg and 2 low 60V legs, you have a problem, be it the rack or something else is up for grabs. I have a hard time believing you would actually have 2 phases that are 60V to neutral.

I would not do any further test with it, I would power it down until you can get a certified tech, or electrician in there. Even lock it out.