Volvo ECS - Page 121

121
ECS Gen. 2
ECS Gen. 1
solenoid valve
operation
A. Basic bellows air flow solenoid.
B. Control solenoid - found only in valve block for drive
axles.
DE. Solenoid ʻDe-energisedʼ. Negative to one pin.
No air can pass through the valve.
E. Solenoid ʻEnergisedʼ. +24V supplied to one pin, negative
supplied to other pin. Air can pass through the valve.
DE. Solenoid ʻDe-energisedʼ. Negative to one pin.
Outlet (2) is connected to exhaust (3). No air can pass from
inlet (1) to outlet (2).
E. Solenoid ʻEnergisedʼ. +24V supplied to one pin, negative
supplied to other pin. Inlet (1) is connected to outlet (2). Air
can pass through the valve.
A - solenoid de-
energised
A - solenoid
energised
B - solenoid de-
energised
B - solenoid
energised