The 120 VAC wiring use for 325 VDC - safety?

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rknelectric

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Researchers wanted to test their new LED lighting system in the existing conference room. The room lights are fluorescent T8, 120 VAC. New LED strips will be installed inside existing luminaries and fed from the power conversion box 325 VDC via existing wires (no neutral - one wire is +162.5V, another -162.5V). Existing wires will be disconnected from the panel and connected to the power box via pull box and protected with fuses. The power conversion box will be fed from the same 15A CB in the panel. Is there any danger/safety issues with this installation? Thank you in advance.
 
rknelectric said:
Researchers wanted to test their new LED lighting system in the existing conference room. The room lights are fluorescent T8, 120 VAC. New LED strips will be installed inside existing luminaries and fed from the power conversion box 325 VDC via existing wires (no neutral - one wire is +162.5V, another -162.5V). Existing wires will be disconnected from the panel and connected to the power box via pull box and protected with fuses. The power conversion box will be fed from the same 15A CB in the panel. Is there any danger/safety issues with this installation? Thank you in advance.
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What voltage is feeding this?


Welcome to the forum.....:thumbsup:
 
Seems ok to me as long as all wires are rated for the voltage. Probably should label this as the voltage isn't what an electrician would
be expecting if they had to work on it. I can see it now....a guy uses a wiggy or a meter set on AC thinking it's not live. And then comes
the surprise:blink:
 
Aleman said:
Seems ok to me as long as all wires are rated for the voltage. Probably should label this as the voltage isn't what an electrician would
be expecting if they had to work on it. I can see it now....a guy uses a wiggy or a meter set on AC thinking it's not live. And then comes
the surprise:blink:
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Agree. Wires rated 600 V. I am going to request to label all luminaires that there is 325 VDC. Also, I think, it needs to test wiring for the new voltage to make sure there are no weak splices/damaged insulation. Thank you!
 
rknelectric said:
Agree. Wires rated 600 V. I am going to request to label all luminaires that there is 325 VDC. Also, I think, it needs to test wiring for the new voltage to make sure there are no weak splices/damaged insulation. Thank you!
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We feed lighting at 277 volt and 480 volts often, Canada uses 347 and 600 volt often.

There is no reason to be concerned with the splices or insulation unless they are damaged before.
 
rknelectric said:
Researchers wanted to test their new LED lighting system in the existing conference room. The room lights are fluorescent T8, 120 VAC. New LED strips will be installed inside existing luminaries and fed from the power conversion box 325 VDC via existing wires (no neutral - one wire is +162.5V, another -162.5V). Existing wires will be disconnected from the panel and connected to the power box via pull box and protected with fuses. The power conversion box will be fed from the same 15A CB in the panel. Is there any danger/safety issues with this installation? Thank you in advance.
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This isn't really 325VDC, this is rectified 120VAC with a plus and minus reference to zero. When we call something that is AC "120V RMS", it too is alternating from zero to 120V RMS + to zero, to 120V RMS- But we don't call that "240V RMS" just because there is technically 240V difference between the two peaks.
 
iwire said:
We feed lighting at 277 volt and 480 volts often, Canada uses 347 and 600 volt often.

There is no reason to be concerned with the splices or insulation unless they are damaged before.
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Looks logical. We have those 277 V lighting as well. But this one was originally installed, including switches, as 120 V. Good thing, all ballasts will be disconnected and only wires, switches and luminaires' hardware be used. Technically, seems there are no issues except labels.
 
Aleman said:
Seems ok to me as long as all wires are rated for the voltage. Probably should label this as the voltage isn't what an electrician would
be expecting if they had to work on it. I can see it now....a guy uses a wiggy or a meter set on AC thinking it's not live. And then comes
the surprise:blink:
Click to expand...

Doesn't a wiggy/Knopp read DC?
 
rknelectric said:
Looks logical. We have those 277 V lighting as well. But this one was originally installed, including switches, as 120 V. Good thing, all ballasts will be disconnected and only wires, switches and luminaires' hardware be used. Technically, seems there are no issues except labels.
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The switces may or not be rated for that use.

Labels are not required.
 
iwire said:
The switces may or not be rated for that use.

Labels are not required.
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Hmmm, will check tomorrow for the switches rating. Thank you.
Why do you think those labels on the luminaires are not required? I just thinking: entire building on 120 VAC, and only one room contains 325 VDC (lighting panel in this room, still 120 VAC). I agree, this is the only test place in the entire campus... maintenance electricians should be aware... but if?
 
rknelectric said:
Hmmm, will check tomorrow for the switches rating. Thank you.
Why do you think those labels on the luminaires are not required? I just thinking: entire building on 120 VAC, and only one room contains 325 VDC (lighting panel in this room, still 120 VAC). I agree, this is the only test place in the entire campus... maintenance electricians should be aware... but if?
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I think it is a good idea to label the fixtures, but I an not sure that the code requires that.

Depending on how the source of the 325 VCD is set up (is the DC circuit a branch circuit) 210.5(C) may require the conductors to be identified as to system and polarity.
 
don_resqcapt19 said:
I think it is a good idea to label the fixtures, but I an not sure that the code requires that.

Depending on how the source of the 325 VCD is set up (is the DC circuit a branch circuit) 210.5(C) may require the conductors to be identified as to system and polarity.
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You are right, hot conductors become positive, and former neutral become negative wires.
 
rknelectric said:
.... New LED strips will be installed inside existing luminaries and fed from the power conversion box .... Is there any danger/safety issues with this installation? Thank you in advance.
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Danger/safety issue 'no' but violation of 110.3 (B) 'yes' unless manufacturer of lights allows that install.
 
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