EAS Electric Inflation O'ride

[RANDLOVER]

A note of warning to anyone trying to force air into the bags by bridging power to the valve blocks, they seem to be pulsating valves and can be damaged by sustained power, the wiring diag doesn't mention this and the only similar description of operation I can find is an old post in the RR P38 section which says:

"Applying constant voltage to the individual valve solenoids may shorten their life a bit... they're designed to be driven by a pulsed current. - Known in some circles as a 'Hit & drop'. That is, a long 12-volt pulse is applied first, this stays on for a pre-set time, enough for the solenoid to pull all the way in, then the current is pulsed at a high frequency, with a 50% duty-cycle. - Effectively 6~8 volts. This is to hold the relay/solenoid in place, which needs less magnetic force to accomplish."

[northiam]

Its called "pulse width modulation"

What is PWM? Pulse Width Modulation tutorial! - YouTube