What is low voltage AC bus voltage for Agriculture unit?

cupoftea

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Hi,
The following Agriculture unit has loads of LED lights to
help the crops grow....


They feed the LED drivers from the output of multiple 6 pulse three phase
diode rectifiers. -With only low capacitance at the rectifier outputs. (its easy to have low capacitance at output of 6 pulse rect and still hold the voltage up well).

So...3 phase Mains comes in to the installation, then a 3 phase transformer steps it
down to , I think, some 50Vrms in each phase_to_neutral....then a frame/network of bare alu bus bars ports this
"low voltage" AC bus around, and then the LED drivers (with their 6 diode rectifiers at their front end) connect to the bus bar with simple screw on "pegs" with flying wire
to the LED driver.

The thing is, we need to know what is the "low voltage" AC distribution bus voltage?
We wrote to them but as yet no answer. Do you know what it is likely to be?
Obviously it will be as high as possible allowed by the SELV regulations.
But what may we ask is that?

It (the bus bar network) obviously needs to be touchable as staff will have to "Peg" LED drivers to it.

How would they allow it to be touchable during a mains transient?, which would be passed through the mains transformer.

The power bus is explained in here...
 
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50 V is in the range we generally hear at Edaboard when low voltage becomes high voltage. Or if the peaks are 70V then I guess that's getting close to overcoming our skin resistance. Gloves ought to be worn as a precaution. Avoid puddles. Use wooden ladders. Keep one hand in a back pocket when touching wires.
 
Thanks, as you imply, anything over 50V is getting dodgy.
A phase would be 50Vpk if Np/Ns was 6.7 or so..but thats from 240VAC....
But then you'd need to account for the mains swelling up to 265VAC...and also for "loss of neutral" when the 3 phases are unbalanced.

Aswell as any mains transient peaks.
The plant picking staff may touch these bare bus bars, and so the voltage of them is pretty crucial, or rather, the standards tell us so.
We are keen to know as we wish to order one of these units for our crop growing exploits.
 
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