This is a question for all the UL gurus, regarding a hardwired (not pluggable) UPS.
The magenetic devices in the UPS will cause leakage current through the UPS ground. I am trying to find out 1 - how much ground current is allowed, and 2 - what is the spec that applies here.
We have looked through UL1778, which is the standard for UPS systems and it uses 60950 as the reference document.
So far, we have seen specs for the allowable TOUCH current, but something tells me that this is different than the ground leakage current. I interpret the TOUCH current to be the amount of leakage that would flow through a person in parallel with the ground wire. So question 3 - what is the definition of TOUCH current?
The magenetic devices in the UPS will cause leakage current through the UPS ground. I am trying to find out 1 - how much ground current is allowed, and 2 - what is the spec that applies here.
We have looked through UL1778, which is the standard for UPS systems and it uses 60950 as the reference document.
So far, we have seen specs for the allowable TOUCH current, but something tells me that this is different than the ground leakage current. I interpret the TOUCH current to be the amount of leakage that would flow through a person in parallel with the ground wire. So question 3 - what is the definition of TOUCH current?