Hello to the group ! I have a pair of data shield at-800's I was wondering if there is a voltage adjust on them .. the batts get down to about 19 volts then the UPS dies I am only getting a run time of aprox 20 min . off this unit .. I had a 'good ole' ups and she would run under full load for 45 min with smaller batts .. Looking for any and all info .. Thanks Rick Szajkowski VA3 RZS Charlotte Darby VA3 CMR Node Owners of IRLP Node 2120 Lakefield Ont Canada