Motoman PX2750, Manual

Page: 132 / 611

9.3 Maintenance and Inspection of the Pneumatic Unit
9-15
HW0480633
9.3
Maintenance and Inspection of the Pneumatic Unit
9.3.1
Solenoid Valve
Check if the air purge starts a few seconds after turning ON the power to the XRC and if it
ends approximately 11 minites later.
9.3.2
Pressure Reducing Valve
Measure the air pressure for the pneumatic unit with a pressure gauge. Remove the test plug
or the relief valve on the pneumatic unit and connect the gauge. The air pressure must
always be from 0.02 MPa (0.2 kg/cm
2
) to 0.04 MPa (0.4 kg/cm
2
) under normal conditions, and
from 0.3 MPa (3.0 kg/cm
2
) to 0.45 MPa (4.5 kg/cm
2
) when purging.
9.4
Inspection of Explosion-proof Devices
9.4.1
Pressure Switch
Remove the front cover of the pneumatic unit box and check the conduction of the pressure
switch. The pressure switch must be ON when the air is being supplied and OFF when the air
is not being supplied.
9.4.2
Master Valve
While the air is being supplied from the pneumatic unit, check if the air purge starts a few sec-
onds after the power to the XRC is turned ON. Also, check if the air goes out of the two air
outlets for the master valve during the air purge.
• Be sure to turn OFF the power to the XRC before inspecting the pressure
switch.
• Do not touch the pressure setting dial on the pressure switch during an
inspection. Changing the setting prevents the correct pressure from
being detected.
CAUTION