During loading
When the net pressure decreases to the lower limit of the working pressure (loading pressure), solenoid
valve (Y1) is energised. The plunger of solenoid valve (Y1) moves against the spring force opening the
control air supply port to unloader (UA).
Phase Description
1 Atmospheric pressure is allowed through solenoid valve (Y1) to chamber (1) of unloader
(UA). As this pressure is higher than the pressure in chamber (3), full-load/no-load valve
(TV) starts opening.
2 Intercooler pressure is building up causing diaphragm (4) to switch to the right. As the
pressure difference between chambers (1 and 3) increases, plunger (2) moves further
against the spring force until full-load/no-load valve (TV) is fully open and unloading
valve (UV) closed.
Air delivery is resumed (100%), the compressor runs loaded.
Instruction book
2920 1815 04 35