Engine idle speed adjustment solenoid valve

ENGINE IDLE SPEED ADJUSTMENT SOLENOID VALVE

The solenoid valve, fitted on the butterfly casing, intercepts the flow of air which, coming from the air upstream of the butterfly, returns it downstream: it has the task of ensuring the additional air for the engine with the butterfly closed, in all conditions where it is required (idle, deceleration).

The valve is the proportional type where the shutter is fixed to a metal core surrounded by an electrical winding.

Operating principle

The position of the shutter depends on the intensity of the effective value of the current passing through the winding which creates a magnetic field which attracts the core.

The vairation in the effective value is obtained by modulating the winding electrical supply (operation in duty-cycle).

This operation consists of varying the battery voltage value (12 Volt nominal) until zero at a frequency where the shutter is not capable of moving following the instant voltage value, but reaches an intermediate position which depends on the proportion between the voltage presence time and the absence time.

Operation in duty-cycle

A: mainly OFF signal = low effective value
mainly ON signal = high effective value
B: effective value

V:

Wiring connector