I've been unable to find a white paper on the best practice for wiring up an InRow RC....
My question is does APC recommend direct connection to mains/utility supply or connection to a generator?
GIven that the InRow RC has dual power inputs for redundancy, we chose to put one input on UPS (which is identified as the "default" source in the configuration), and the second on utillity power. Both sources are on generator backup so we have the best of both worlds. Additionally, we have six inrows in this particular room so for those UPS fed inputs, half are on the A ups and half on the B ups so we have multiple redundancies.
I guess you have 2 different power paths in your DC, backed up by UPSs, so the RCs should be connected to them.
The absorb just around 500W (ours are running at 350W - 400 W ), so you shouldn't encounter issues.
I would not connect them directly to a utility/generator path, since spikes (when the gen kicks in) could destroy the electronics and you could finish with an overheating DC.
The generator facility for this particular site has a closed-transition transfer switch so there are no transients/bumps in whats incoming. But you are correct that it might not be too healthy in the long run to have RC's direct off an open-transition setup...I wonder if the RC has MOVs or other filtering in its power supply. Perhaps APC could answer that. We have several FM series AC's on open transition transfer switches going on six years now with no problems. Most of the electronics in these operate off a group of toroidal step down transformers so that in itself offers protection.
A data center with no cooling will overheat at an extreme rate. If you have the data center UPS on the generator your cooling should be as well.
The RC units require so little power I've seen them on the UPS quite often.
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