General Operation - WEBTEC DHM 4 Series Manual

All tests should be performed by suitably qualified personnel.
1. Connect the Tester to the circuit (see above for installation guidance)
2. Ensure that the pressure loading valve is fully opened by turning the knob counter clockwise.
3. Switch the unit on. On digital models if the display flashes then the battery needs replacing.
4. Select the desired test using the front panel controls.
5. IMPORTANT: Ensure that all connections are tightened and the oil can flow freely throughout
the hydraulic system BEFORE running the machine at full speed. Check that the circuit is
correctly connected and any shut-off valves are opened. Also quick disconnect couplers
MUST be open.
6. Start the pump momentarily to ensure there is no obstruction which could cause pressure
build up.
7. Check for leaks and free flow of oil
8. The tester is now ready for use - run the machine and adjust the loading valve as needed
9. When the test is completed fully open loading valve.
Notes
When low pressure testing is required, connect the optional low pressure gauge with automatic
cut-out valve to the tester block.
Testers have an automatic electronic system which shuts the power off after approximately 20
minutes of inactivity should you forget. To reactivate the tester press the power button.
Performance
All 800 models have limited pressure control below 86 lpm (23 USgpm). The maximum
controllable pressure in this region is calculated by: Max. pressure (in bar) = 5 x flow (lpm) +30.
Do not use with water
The standard Webtec Hydraulic Testers are designed for use with mineral oil having reasonable
lubrication properties. They are not suitable for use with water or fluids with a high water
content. If a tester is contaminated with water it should be flushed immediately with white or
methylated spirit or similar and then flushed with mineral oil to minimise any internal corrosion.
This may avoid an expensive repair. Damage to a tester from the use of a non-approved fluid
invalidates our normal warranty.

General Operation

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