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Per Jessen wrote:
Depends on how many you have. The typical battery used in large scale UPS's (for bridging whilst the generators get going) is a 24v truck battery. I have no idea how much such a collection can deliver, but when it needs to run cooling, lighting, disks and e.g. 3-4 IBM 3090s of the old kind, it's quite a bit. Usually they're only designed to hold the load for 5-10minutes though.
Batteries used for starting cars & trucks are not suitable for that type of service. Starting batteries are designed for high current, short term loads. Batteries for UPS are designed to be floating on the rectifier output and be ready to take over the load immediately and sustain it for as much time as required. Typical UPSs, as used with personal computers only last several minutes. Those used for telecom etc. have to carry the load for several hours or even days. Using the wrong type of battery may work in the short term, but premature failure is pretty much guaranteed. In the telecom office where I used to work, there were several battery strings and multiple rectifiers to keep them charged. If the commercial power should fail, standby generators would kick in and last as long as the fuel held out. As I recall, each cell was almost a metre tall and 50 - 60 cm square. They were mounted on steel racks and connected with very large cables. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org