MTS Hydraulic Power Unit Model 506-92 - Manual (Page 24)

3-12 Service
3 . 2 . 2 Dual-Temperature Switch Adjustments
Definition The dual-temperature switch has two adjustment screws behind its front
protective cover. The Over Temperature adjustment turns off the HPU if
hydraulic fluid reaches a temperature of 140˚F (60˚C).
The Water Solenoid Control adjustment allows water flow to the heat
exchanger when an oil temperature of 105
°
F (40
°
C) is exceeded. The water
solenoid control is only used if the optional water solenoid valve is
required.
WARNING !
Do not touch the dual temperature switch’s electrical leads.
They carry 120 Vac. Touching them could give you a serious or even fatal
shock.
Perform this procedure wearing insulated gloves and using an insulated
screwdriver.
VW-G042E
HPS – Rear View
adjustment screws
Dual Temperature Switch – cover removed
temperature gage
DO NOT TOUCH!
(read the Warning)
Before you begin Turn off the HPU. Loosen the screws on each side of the switch assembly,
and pull the front protective cover off. The adjustment screws are labeled.
Over-temperature
adjustment 1. Turn the over-temperature adjustment screw (figure above) several
turns clockwise to raise the temperature limit.
2. Turn off the water supply to disable the heat exchanger.
3. Turn on the HPU and apply high pressure (see Subsection 2.2).
4. When hydraulic fluid temperature reaches 140˚F (60˚C), as
indicated on the temperature gage, turn the adjusting screw
counterclockwise until the HPU turns off.
5. Turn on the cooling water supply.