Power Supply: AC 240V 50/60Hz Stand-by Battery: DC24V Sealed Maintenance-Free Lead-Acid Battery Charging Voltage: DC26.4V Below 450mA Trickle Charging Circuit Voltage: DC24V Short Circuit Voltage 5V below 32mA Loop Resistance: Below 50+ back and forth Detector Installation: No limit in the number of differential detector & constant-temperature detectors used; smoke detectors or electronic differential detectors; each ciruit can connect to a maximum of 16 smoke detectors (monitoring current for detectors: DC24V 40¦A) Terminal Resistor: 10k+ Number of indicators: 1 time the number of panel circuits Number of Local Alarm: 1 time the number of panel circuits. Number of circuit & Dimension: 1L/2L/4L/5L/8L (330x280x120mm) 12L/16L(400x300x120mm) 24L(495x300x120mm).