Lew Wolfgang wrote:
On 1/27/21 1:42 PM, Carlos E. R. wrote:
My experience with UPS may be limited, but back in the day I ran a 10-KVA UPS to power a group of Sun Microsystem servers. It was a nice UPS with a ferroresonant transformer that conditioned power as well as running the 10-KVA load for 30-minutes. In my experience, we experienced more unplanned power outages caused by the UPS itself than if we directly connected to the mains. After we retired the Suns and switched to SuSE I once managed to keep the main server up and running continuously for a bit more than 4-years, without the UPS. Without a reboot! It was a busy server too, with a hardware RAID controller. Do you remember how did the UPS fail? I'm curious.
The UPS never actually failed, except for a time or two when the battery bank needed to be replaced.
Downstairs we have a couple of APC SmartUPS'es - they know very well when the batteries are due :-) They will sound an alarm, send an email and an SNMP alert and keep doing it until the battery "cartridge" is replaced. Once you pull out a cartridge, the entire bank is disabled, which reduces the runtime by 20%. At home, I have a little 6kVA Eaton, it's a little more effort. To swap the batteries, you have to take the front off and switch it into bypass, for instance. With monitoring by NUT, I still get SNMP alerts though - not sure if it actually will complain about batteries, but it does complain if the runtime sinks below a certain threshhold. Still, it is really off-topic. -- Per Jessen, Zürich (3.0°C) http://www.dns24.ch/ - free dynamic DNS, made in Switzerland.