Symmetra PX 80kVa Recharge Draw

[lightspeedhosting]

We have a 80kVa Symmetra PX unit with 2 battery frames filled. We usually have a load of around 30%, we don't push it very hard.  Most we ever had loaded on it was about 40%.

We had a recent outage and the output breaker on our generator tripped and we're doing some calculations to see if the building load might have tripped it or if it's possible that there was a ground fault (it was raining hard).

The breaker we have for this unit at the panel is a 150amp at 480v which is what is specified in the installation guide.  What is a reasonable draw for this unit when the generator is running and the UPS is recharging it self while also serving our current load profile?

[al_buffington]

Hi,

150A is the correct breaker value if you have a 480V source feeding a PDU w/ bypass that is stepping down the voltage to 208. The battery charging power for the PX80 is 1kw per power module. The typical draw would be whatever your load is plus 9kw (this assumes you have a redundant power module). There is an option to disable battery charging while the generator is running (through a dry contact) but this would require field service involvement to enable. This feature is only available with intelligence module firmware version 17.0 and higher.  I hope this answers your question.