Hi itsmoked,
It's not so much 'how many devices per supply', since we usually only have one big DC supply, the site UPS. This gets divvied up in the DC panel, which then provides individual DC supplies to local PLC chassis with their associated I/O.
AFAIK we usually don't have more than one...
Thanks for the pointer, stevenal!
I'm checking out these Hindle chargers now...they're pretty slick! They are a bit bigger than I was hoping for (I was angling for something more the size of Phoenix Contact's DIN-rail mountable Quint supplies), but hey, they do integrated GF monitoring and...
Thanks itsmoked, for throwing down the metaphorical gauntlet! If that doesn't get responses, nothing will!
As to why we need this: we leave both poles of the DC supply floating when we serve 24VDC power to our PLC's and end devices (sensors, instrumentation, etc.). This has two benefits that...
Hello,
I was wondering if anyone knows where I could find a mid-sized (about 30A, 750W) 120VAC to 24VDC power supply that has integrated ground fault monitoring of it's floating DC output with remote indication? Din-rail mountable would be a bonus, but not necessarily required...
I can find...
Thanks mc5w!
I forgot to mention, we left the CT at the utility entrance, we just switched around the phases of the capacitor tie-in (therefore, the PT phase) at the sub-MCC. So the controller is detecting all reactive site current, and since the DLRO testing between the main MCC and the...
Aha!
Further site investigation revealed that the CT was on Phase B rather than Phase A, while the controller was hooked up to monitor Phase A for voltage. No wonder the controller kept trying to switch them all in...
Phase B was chosen by the field installation team because it was the most...
Thanks for your input, windie!
I didn't consider the fact that the correction bank controller needs to see both current and voltage at the same point to detect the power factor (duh...). There are also quite a few medium-HP motor branch circuits physically tied into the MCC buss between the CT...
Hello all,
For installing an automatic capacitor bank, I was wondering if it makes a difference where in the power system the sensing Curret Transformer (CT) is located? Does it matter if it's 'upstream' or 'downstream' of the capacitor bank tie-in? Should it be right next to the capacitor...
