MTS Model 506-62-72 Hydraulic Power Supply - Manual (Page 21)

Service 3-9
3 . 2 . 1 Output Pressure Adjustment
HPS – Side View
VW-G044K
pressure
gage
DIRT ALARM
back-up
relief valve
CHANGE
OK
Refer to Figure 3-2 for the location of the components indicated in the
following procedure.
1. Turn off the HPS.
2. Make sure that the output pressure gage reads zero (the figure on
the left shows the location of the pressure gage).
3. Remove the plastic cap on the pump pressure control.
4. Loosen the locknut and turn the pressure control fully
counterclockwise.
5. Loosen the locknut on the back-up relief valve and turn the
adjustment knob fully counterclockwise.
TS-G072
Top View
Backup relief valve
Adjustment
knob
Locknut
6. Start the HPS in low pressure, then switch to high pressure.
7. Observe the pressure gage and alternately turn the back-up relief
valve adjustment and the pressure control knob clockwise.
1
Stop adjusting at approximately 500 psi (3.45 MPa) above the
desired output pressure (typically 3000 psi/21 MPa).
8. Tighten the locknut on the back-up relief valve.
9. Turn the pressure control adjustment knob counterclockwise until
the desired output pressure is reached.
10. Turn off the HPS and replace the plastic cap removed in step 3.
N O T E Whenever the output pressure is changed, the
accumulator precharge must also be checked (see
Subsection 3.1.3).
1 Adjustment increments should be approximately 500 psi (3.45 MPa) apart as indicated on the pressure gage.