A 48 volt battery discharged down to 42 volts will be a very very heavy load for whatever is attempting to charge it. A TSP 600-148 will only make 12.5 amps max.
Your battery could easily want 25 or 50 amps for the first 10 seconds. It will taper off to zero as it comes up to charge, but the more dead they are, the more they appear to be a dead short to the charger. You have probably never tried to start this system with stoned batts. What is the amp rating of the battery breaker? And the AC side will have a pretty high inrush current as well. Is your AC breaker greater than the power supply inrush current. TSP 600 recommends a 25 amp circuit breaker on 120 VAC. From: Josh Baird Sent: Sunday, May 28, 2017 10:19 AM To: [email protected] Subject: [AFMUG] Traco TSP+BCM Question I have a site with a TSP+BCM 48V combo. Last night, something caused the AC breaker to trip, putting the site on battery. We didn't see the alert until about 12 hours later. At this point, the batteries were down to ~42V. When our guy arrived on site, he reset the AC breaker, and AC power was restored. Immediately, the battery breaker (breaker between positive side of the batteries and the BCM) tripped. Now, each time that we reset the battery breaker, it causes the AC breaker to immediately trip. At this point, the site is up on AC with no battery. Any ideas what would be causing this? Do you think the batteries are causing the BCM to draw too much current? Could one (or more) of the batteries be dead/bad? The site *did* run successfully on battery for nearly 12 hours. Josh
