4 ms·
> this is no different from using a dumb, unprotected PDU I would caution that depending on exactly what electrical components are inside the PDU, under certai
by Reelin 6y ago
> this is no different from using a dumb, unprotected PDU
I would caution that depending on exactly what electrical components are inside the PDU, under certain conditions (say, on plugging it in) it might briefly draw much more current than you would naively expect. (Based on the picture they posted though I doubt that's the case. It looks fairly "dumb" to me.)
For example, "I'll plug this UPS rated at 50 amps into a 20 amp circuit. It's fine because I'm only attaching 10 amps worth of equipment to it!" is unlikely to go well depending on (among other things) the rate at which the batteries charge.
- nucleardog 6y agoBriefly drawing more power would not really be an issue. Circuit breakers don’t operate as binary devices in the sense that a 15A breaker works indefinitely at 14,999mA and then turns off at 15,000mA. They usually use a bimetallic strip to provide a gradual response (more current = more heat = faster trip) with an electromagnet actuated trip that creates an absolute limit. See, for example, this PDF: https://download.schneider-electric.com/files?p_enDocType=Data+Bulletin&p_File_Name=0600DB0105.pdf&p_Doc_Ref=0600DB0105 https://download.schneider-electric.com/files?p_enDocType=Da... Even at double the rated current you’re looking somewhere around 30-90 seconds before it trips. If this weren’t the case, we’d be tripping breakers every time we fired up a stand mixer or a vacuum cleaner.
- Lammy 6y agoYep, this is a totally dumb one. It is actually labeled "24 amps max, 20 amps max per outlet, 20 amps max per bank", hence the NEMA L5-30P so it can try to make sure that guarantee means something: https://download.schneider-electric.com/files?p_enDocType=CAD&p_File_Name=RZAN-6BZQAK_R2_EN.pdf&p_Doc_Ref=SPD_RZAN-6BZQAK_EN https://download.schneider-electric.com/files?p_enDocType=CA... The "banks" are just one half each of the total outlets. The PDU's lil segment display flashes between the integer-rounded Bank 1 load, Bank 2 load, and Banks 1+2 load, and the same data is available with more precision through the serial or Ethernet ports. I have my beefy workstation and NAS on the bottom bank and all my network gear on the upper bank, so right now my PDU is flashing between "3", "0", and "4" amps respectively (rounded): https://i.imgur.com/o50UJoO.jpg https://i.imgur.com/o50UJoO.jpg Honestly I'd be more worried about fire hazard if I used an equivalent “legit” setup with three power strips and three Kill-A-Watts.