UPS supply

[SoulTy1066]

Been to look at a job for a client who has acquired a large EATON powerware 9390 UPS. Any tips on installing this? It will control the 3 phase D/B for his large computer suite.

 

[SW1970]

Have you done one before? Pricey item. Normally a job for a reseller. The documentation is on the Eaton website. It sounds from your post that it might be a used item. If it is, before you lay a finger on it, make sure client understands in writing that batteries might have had it and need replacing (loadsamoney). In my experience batteries in these things last circa 3 years with monthly cycling. If client wants to use the remote features, it's quite complex and you might need to call in a reseller for some of that.

 

[oxocube]

There are many things to consider, SW has mentioned the batteries, but how many do you need? how long do they have to last (autonomy)? is there generator back up? or is the batteries purpose just to allow an organised shutdown?who is going to commission and guarantee the ups? are you providing an external ups bypass circuit? will additional air conditioning be required?

I would contact Eaton and get theire advice and assistance, including commissioning and maintenance costs.

 

[tlangdon12]

Has the client asked for an external maintenance by-pass? (They need one, but it needn't be the expensive, matching, Eaton one). Ideally the by-pass should rated to the max current that the supply cable will carry, to allowing additional UPS units to be added without having to uprate the by-pass.

The maintenance by-pass can also include a provision to connect a generator to the UPS, something that can be useful in the event of a planned, long-term power outage.

I would definitly plan around the installation of a second UPS at some point in the future, either for expansion or greater redundancy. So plan the siting of the unit and cable routing to allow for this. Additional battery cabinets may be needed to extend run-times.

Does the client know how long it would take them to conduct and orderly shutdown of all the equipment in the Data Suite? They should be encouraged to work this out and add 30 minutes to this time to get the required runtime that batteries need to handle - 30 minutes is now long it will take them to bite the bullet on the need to start an orderly shutdown!

Most computer equipment used in data centres requires multiple power inputs, so feeding these from two UPS provides additional redundancy AND, more critically, allows one UPS to be powered off for maintenance. Having a Maintenance By-pass allows the equipment to still draw power from both PSU, providing protection against the one active UPS failing. (Note this arrangement requires both UPS to be run at no more that 50% load).

The DB will need labels stating that it is fed from a UPS and will remain live when the mains supply has failed. A notice of where the UPS supply to the DB can be shut off should also be in place.