In this episode of the DC Power Hour David and Allen introduce Ed Rafter, a special guest on DC Power Hour, who is an expert in UPS batteries. They discuss the differences between ups and downs, voltage, discharge times, and other aspects of battery powering. Ed has a 40-year career in mission-critical applications, focusing on batteries. He first learned about batteries in the 1980s when he worked for an engineering firm in New Jersey and then worked for data centers for the New York and American Stock Exchange and securities industry. Allen shares his experience installing dry charge batteries in Saudi Arabia in the late 70s.

Episode Highlights

01:06 – UPSs are now probably one of the largest users of batteries in this country. But there's a lot of differences between UPSs and other types of powering, and we'll go into that, you know, differences in voltage, discharge times, whole slew of stuff.

08:24 – When I first was introduced to the battery, we used to size them for 30 minutes. That was pretty common as part of that was if all hell broke loose, we wanna make sure that the UPS stays online so we can either recover, figure out what went wrong, and see if we couldn't recover or have enough time so that we might be able to quiesce the system.

30:09 – I think it was the first time I heard somebody got killed. It was one of the manufacturers, one of their people working in a battery cabinet. I had known of people getting hurt working on the racks, the open racks.

42:33 – Now we're talking about bidirectional inverters. So instead of having a very large substantial rectifier that's gotta not only serve its critical load, but keep the battery charged.