Table of Contents
Advertisement
Instruction book
Reference
A
R
1
2
3
4
Unload mechanism
The pilot valve is equipped with a hand-operated unload mechanism: by turning the red handle (1) 90
degrees, the plunger of the valve will be lifted, releasing the spring force. The air pressure from the
pulsation dampers will force down unloader plunger (8) and the compressor will run unloaded. By
turning handle (1) 90 degrees further, the plunger returns to its original position so that the pilot valve
will again unload and load the compressor at the pre-set pressures.
Setting of the pilot valve
The maximum pressure is controlled by adjusting screw (2):
1.
Loosen handle (1) and the two nuts (3)
2.
Turn the adjusting screw (2) clockwise to increase the maximum pressure.
3.
The pressure difference can be increased by removing one or more shims (4).
4.
Fit the two nuts (3) and handle (1) in their original position.
6.7
Safety valve
Replace the valve if it does not open at the correct pressure. No adjustment is allowed.
Testing: Testing as described below shall only be carried out by competent personnel.
If safety valve is not used for longer than 6 months, pressurize for 4h to have working
pressure.
Testing
1.
Close the air outlet valve, depressurize and disconnect the hose or pipe from the valve
2.
Start the compressor and run it until it stops automatically.
3.
Switch off the voltage.
Remove the cover from the air pressure switch and, with the air receiver now under pressure, turn
the adjusting screw one turn clockwise to increase the stopping pressure Adjustment of MDR4S
pressure switch and Adjustment of MRD3 pressure switch. Reinstall the cover.
4.
Switch on the voltage, slightly open the outlet valve and start the compressor
5.
Gradually close the outlet valve while checking the air pressure gauge. If the safety valve has not
opened at the pressure specified in Compressor data, it must be replaced by a new one. If the
compressor unloads before the specified opening pressure is reached, repeat the procedure as
mentioned from step 3.
6.
Readjust the unloading pressure as described in sections Adjustment of MDR4S pressure switch
and
Adjustment of MRD3 pressure switch
7.
Reconnect the hose or pipe to the closed air outlet valve
2920 7089 80
Description
Control air to unloader
Vent hole
Unloading handle
Pressure adjusting screw
Nuts
Shims
65
Hide quick links:
Advertisement
Table of Contents
