Insights
Field notes on designing, installing and keeping security systems running, written by the people who do it.
-
An access control power supply is sized for the worst minute, and its battery for the longest hour
How to size an access control power supply and its standby battery: continuous versus energized loads, simultaneous unlock, derating and voltage drop.
-
A 30-day retention requirement is a storage problem, not a camera problem
How to size video storage so a recorder really holds the retention the contract requires: bitrate, duty cycle, TB versus TiB, RAID overhead and headroom.