[Attachment: High-Pressure Safety Valve Adjustment Procedure] - Daikin SUT10D80L21-10-F Operation Manual

PIM-00004△1

[Attachment: High-pressure Safety Valve Adjustment Procedure]

With this hydraulic unit, it is not necessary to change the high-pressure safety valve settings in detail, even in
the case of pressure setting adjustment. This hydraulic unit uses the IPM motor, resulting in drastic
improvement of the motor drive system. Thus, it ensures stable performance without necessity of high-pressure
safety valve setting adjustment.
In any of the following three cases, adjust the safety valve with reference to "Safety Valve Adjusting
Procedure".
1. When safety valve setting adjustment is required:
Even if the hydraulic unit is used with the maximum pressure setting, the safety valve will not be activated
under normal pressure control (except for the transient period when the circuit is blocked due to stop of the
master machine hydraulic actuator). However, the safety valve set pressure will be lowered due to long-term
repeated operations and contaminants in the hydraulic oil. If the safety valve is activated even with normal
conditions, safety valve adjustment is required.
[Judgment criteria]
The hydraulic oil temperature rising time is shorter than before.
When the safety valve adjusting screw is turned in the tightening direction, the rpm indication in the
pressure hold status is lowered.
2. To minimize surge pressure that much exceeds a set pressure, safety valve adjustment is required in
consideration of the withstand pressure of the hoses being used.
3. When the pressure set value is changed from the factory setting:
In order to suppress surge pressure to protect the master machine peripheral equipment (actuator, pressure
gauge, etc.), it is recommended that the safety valve set pressure should be set "pressure of the unit + 1.0
MPa".
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