The 12VPS (item # 369) is a "regulated" 12 volt DC power supply.

Input to the 12VPS should be 14-20 volts AC (16vAC typical, Item# 690) which can come from the accessory terminals of most power packs or from a separate transformer.

The 12VPS is "regulated" so it can supply a consistent 12 volts DC to numerous devices regardless of how many of these devices are activated at any one time.

The 0.5 Amp output of the 12VPS is equivalent to 10-15 devices such as the TRAK­DT family, OPTO­DT, and the KEEP­A­LIVE.