The M1 has 1 AMP of continuous Current available and during alarm 2.5 AMP with the additional current being drawn from the battery. The 1 AMP continuous is a combination of the +VKP, J16, +SAUX and +VAUX terminals. You can check the system current draw from a keypad Menu 8, 86-System Diagnostic, 2:Sys Volt/Curr. If the current during normal operation (not in alarm) is above 1 AMP you will need a secondary power supply.