UPS BACKUP LOCATION

[VENgineer]

Hello everyone, I hope you can help me with the following question.

I am designing an electrical installation for a small casino, and I am developing the installation architecture. However, I have a question about the UPS. Due to the client's requirements, all the load must be backed up by a generator and UPS. My question is whether I can connect the input and output of the UPS to the same panel. I apologize for my ignorance; this is my first project incorporating backup systems.

I am an engineer 1 in my company, and next week, my supervisor will review it. I just want to make sure I am not delivering something nonsensical.

Thank you very much. I have not added the ampacities of the equipment or conductors in the picture; for now, I just want to clarify my doubt about the architecture. Thank you.

 

[ron]

The UPS is not able to be connected like that.

Have the ATS-GMR feed a panelboard that serves the input to the UPSs (they need to be designed to operate in parallel in your application) and bypass, then the output feeds another panelboard which goes out to serve the load.

 

[zbang]

The output of the UPS usually goes to "critical load" panels, which are separate from generator- or ATS-supplied panels. Also, your drawing does not show any maintenance bypass for each UPS (to run utility power around it when under maintenance).

Something else to consider is whether some areas should be supplied separately by both UPSs, often data centers and the like will have both an A and B supplies, even running redundant power to the equipment racks.

 

[VENgineer]

Thank you for your answers. I understand from what you mentioned that the architecture should be as follows, without delving into specific details yet.

 

[petersonra]

I am guessing the BP input on the UPs is for bypass. Some UPs's have this kind of arrangement so the power can come from a different source during bypass mode, but in your case it is the same source so unless there is some special reason to do so, I don't think you need to get a UPS with a bypass supply input.

It seems in your latest sketch that you have changed the basic design concept to not feed DPHB with the UPS's.

My inclination would be to feed the two UPS's directly from the ATS and get rid of the extra panelboard.

 

[ron]

Thank you for your answers. I understand from what you mentioned that the architecture should be as follows, without delving into specific details yet.

I'm not sure if the size of the UPSs you are referring to operate in parallel, but smaller ones do not. Would you want to separate the output of UPS A and UPS B so there are redundant circuits available to dual input loads?

 

[VENgineer]

I'm not sure if the size of the UPSs you are referring to operate in parallel, but smaller ones do not. Would you want to separate the output of UPS A and UPS B so there are redundant circuits available to dual input loads?

Each panel GM will be connected load approx. 80kva 208V, same for data room panel. Aprox total load 320-400kva. i was thinking about 2 ups 250kw.
Our reference is another casino that the arquitecture is trat one. (2 250kw UPSs to similar loads.)

 

[ron]

If the total load is ~400kVA, then provide a single 500kVA/kW UPS module to avoid paralleling, unless it is a client requirement. Sometimes people will parallel, but it is for N+1 redundancy, so you would need to parallel 500kW units for N+1 redundancy at the module level.
Are there no dual input equipment needing diverse sources?