Batboard

Recently connected a battery backup to a Quantar repeater station. The station was purchased with the battery revert option as all the cabling and connections where present on the back plane. The batteries were never connected to the station for some reason. After connecting the batteries as outlined in the station documentation and checking the station software programming against another Quantar station that all ready had battery revert operation in place, went to test (simulated an A/C failure) the newly connected battery revert option and the station failed. The existing Quantar with batteries worked just fine. After charging the newly connected batteries for more than 48 hours, a second test was performed with the same results as the first. Connections were double checked (inlcuding fuses) and the Quantar station is outputting the correct charging voltage. What did I miss?

Just a guess (as are all long-distance diagnoses), but presuming this is a high power Quantar, it runs on 24VDC, not 12 VDC, which means your two 12V batteries have to be wired in series, not in parallel. If the radio lost AC and saw only 12V on the revert plug, it will shut down.

Sorry I didn't mention those specifics in my original post. The station is a high power transmitter and the station is connected using two 12 volt, lead acid batteries connected in series. Any other thoughts?

Are you monitoring the voltage of the battery string? If it was ever charged then allowed to self-discharge and sit that way for months/years, you're likely in need of new batteries.