Hypertherm HyPrecision 100D Instruction Manual page 36

A pressure relief valve is also included in-line with the filter assembly
(see picture) to avoid inlet pressures above 125 psi. The pressure relief
valve is factory set to 120 psi and should not need adjustment. If either
panel gauges reads over 125 psi, contact an Hypertherm service
representative regarding resetting and/or servicing the pressure relief
valve.
The boost pump is protected from overheating by the PLC control. When there is no demand for cutting
water the boost pump will automatically shut off and not turn on until demand has returned. If the water
pressure falls below the pressure set point of the low-pressure switch the boost pump will resume
operation.
Boost Pump Pressure Adjustment
This adjustment must be made with the pump turned off.
It is factory set to provide correct inlet cutting water
pressure as supplied by municipal water or well pumps. In
cases where the pump is supplied by a tank, such as on a
reverse osmosis system, it is necessary to increase the
boost pressure. The boost pump pressure-relief valve is
adjusted by loosening the jam nut and turning the T-
handled adjustment screw (image at right). Turn clockwise
to increase the pressure or counterclockwise to decrease
pressure.
High Inlet Water Pressure
Inlet water pressure that exceeds 70 psi requires that the boost pump be turned off.
Open the electrical cabinet and turn the switch located on the boost pump motor
contactor to OFF (0).
After turning off the boost pump inside the cabinet, you must also turn off Boost Fault monitoring in the
PLC. This can be done by entering the configuration screen then pressing View Pump Config and
pressing More. Press the button on the screen to change the setting to OFF.
The electrical cabinet contains high voltage. Extreme
care should be used when working in this area. If you
are unfamiliar with this area, a qualified electrician
should be used.
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