Jim, I have a commercial system that still uses Micors with the TPN1105/TPN1106 (with an SP(special - that produced and alarm tone for the operator/dispatcher)) that has been in service since 1975 or so and run on batteries. The batteries used were 6-KCT270 batteries in series and the system run on battery 24-7 without problems with the batteries. Nominal current drain from the supply was equal to the charge of about 200-300 ma maybe a little less, plus the load of two to as many as four Micor radios. On transmit part of the current would come from the battery and the other part from the power supply with one power supply running a site. Old age did and has finally caught up with most of them, but it took 30+ years to finally finish them off. Gel Cells are now used, usually 2 12v 100A in parallel. The float voltage has to be monitored and maintained at the proper level for the battery in use. Usually these were run at nominal 13.5 volt DC. Periodically water had to be added to the KCT270's, but they were mostly checked quarterly thru their life span. A KCT270 was a 270 Ahour 2.2 volt glass cell about 20" high, 14" deep, and 3 or 4" wide, thus the use of 6 of them. I would not hesitate to use one of these with a battery and as long as there was an alarm that notified the user(s) that the power was off and the battery going dead would not necessarily be a problem. I had these particular batteries go for several days (5, I think - due to a tripped circuit breaker - lightning related) because the user didn't know what the beep was on the console. Good grief.
Steve KB3FPN ----- Original Message ----- From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, December 14, 2007 4:34 AM Subject: [Repeater-Builder] Re: power supply / battery system for repeater site I want to thank all that helped guide me to Motorola TPN1105/TPN1106 schematics, back in July 2007. Although, these above schematics are not the Motorola Micor power supply, that I have. They are similar. I have a Motorola Micor power supply, with the float/equilize slide switch for an battery option. I understand from reading a MSR-2000 manual, the power supply can be set for Nicad or Lead-acid batteries. I was mostly interested in a battery cut-off circuit, so the power supply doesn’t over charge the battery. Although, from reading the emails, a over discharge circuit should also be used. Does Xantrex or http://www.newmarpower.com/ have a cut-off & a over discharge circuit? My batteries are awaiting for the properly controlled charger, with as much details. Thanks & 73’s, Jim Kh6jkg. ------------------------------------------------------------------------------ More new features than ever. Check out the new AIM(R) Mail!