This humble little device is a near-relative of the “crowbar” over-voltage protection circuits used in the computer industry – now adapted for use in aircraft electrical systems. Completely solid-state, this quarter-sized, sealed module is capable of taking a runaway alternator “off-line” in milliseconds. This same device is used in every 504-1, 504-2, and 505-1 PM/OV Protection Kit sold by B&C. Available for both 14 and 28-volt electrical systems.
Wiring schematic included.