My safety officer is indicating that we are daisy chaining our UPS’s.?

Anonymous user · ‎2021-06-29

There are two scenarios we are dealing with.

#1

I have a branch circuit outlet, a APC TVSS (model P7GB) is plugged into the branch circuit outlet.

I have a APC Smart UPS 1500 that is plugged into the TVSS.

My Comm. gear is plugged into the UPS.

#2

I have a branch circuit outlet, a APC TVSS (model P7GB) is plugged into the branch circuit outlet.

I have a APC Smart UPS 1500 that is plugged into the TVSS.

My Comm. gear is plugged into the UPS.

A second TVSS (PanaMax) is plugged into the UPS for low draw/dc bricks.

Is this really a problem?

BillP · ‎2021-06-29

Yes, the article focuses on UPSs but some of it still applies for your situation, especially the fact is not UL tested. I did some more questioning with our Surge escalation lead and he did not seem to be concerned but indicated in some locations, this could be considered a "powertap" which is not acceptable in particular locations - not sure if your local code comes into play.

The other thing is the surge within the surge protector and UPS would be in series and in this scenario, the surge protector would likely take the biggest hit.

In summary, we do not think it will be a problem. Only surge protectors connected to the output of the UPS would be a concern for overload reasons and capability of the UPS detecting overloads. On the input, I would just double check with your local code but otherwise, its fine.

See Answer In Context

BillP · ‎2021-06-29

We have some information on that topic here -> Daisy Chaining UPS | FAQs | Schneider Electric US

Could I ask why you are doing this? Generally we see customers connecting surge protectors into the output of the UPS for additional outlets but it sounds like you're doing the reverse of that and I am not sure if the benefit there. The UPSs have surge protection in them as well so my only thought is you are looking for extra surge protection?

Anonymous user · ‎2021-06-29

Thanks for the link... But we arn't chaining UPS's together.

Is the extra surge protection a problem? Smart UPS 1500 = 459 Joules, APC TVSS model P7GB = 1080 Joules.

Is the TVSS off the back of the UPS a problem?

BillP · ‎2021-06-29

Yes, the article focuses on UPSs but some of it still applies for your situation, especially the fact is not UL tested. I did some more questioning with our Surge escalation lead and he did not seem to be concerned but indicated in some locations, this could be considered a "powertap" which is not acceptable in particular locations - not sure if your local code comes into play.

The other thing is the surge within the surge protector and UPS would be in series and in this scenario, the surge protector would likely take the biggest hit.

In summary, we do not think it will be a problem. Only surge protectors connected to the output of the UPS would be a concern for overload reasons and capability of the UPS detecting overloads. On the input, I would just double check with your local code but otherwise, its fine.

Anonymous user · ‎2021-06-29

Thank you for the info. I will look into the State Code about the possible powertap.

Didn't think it was as big of a issue as indicated.