Tools
UPS and battery backup calculator
Work out the UPS or inverter and the batteries a security system needs to keep recording through a power cut. A recorder that goes dark during an outage records nothing at the moment it matters most.
How to read this
Size for the longest outage you want to record through, not the average one. Outages outside town centres often run longer, and a site with a generator still needs enough battery to cover the minutes before the generator takes the load.
Maximum draw is the right basis for sizing. Cameras draw most at night, when infrared or white light illuminators are on, and that is also when most incidents happen.
Lead acid batteries last longest when they are not drained below half their capacity, which is why the calculator only counts half. Lithium batteries cost more, weigh less and can be used more deeply. Either way, protect the recorder and the PoE switch with surge protection on the incoming supply, because the equipment the UPS protects can still be damaged through the network cables.
For recording storage, use the storage calculator.