DH Instruments ADCS-601, Operation And Maintenance Manual

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6. GENERAL MAINTENANCE AND ADJUSTMENTS
Page 117 © 2005 DH Instruments, Inc.
6.4 PG7601, DISASSEMBLE PLATFORM AND REMOVE
MOUNTING POST PRT
It is not normally necessary to remove the mounting post PRT for recalibration. It can be recalibrated
in-situ by comparison with a reference PRT (see Section 7.3.4.).
To disassemble the platform and remove the mounting post platinum resistance thermometer, proceed as
follows:
Remove the piston-cylinder module from the mounting post (see Section 6.6.1) and replace with the
ORANGE storage plug.
Disconnect the PG7000 Platform from the PG7000 Terminal.
Invert the PG7000 Platform so that the bottom of the platform is up. Support the platform so that it
does not tip over. A simple solution is to place the platform upside down on a sturdy box which is
smaller than the outside platform dimensions and is also tall enough to allow the mounting post to
be suspended.
Remove the six socket head screws (3 mm) around the perimeter of the platform.
Lift the base cover plate gently and carefully disconnect the sensor leads at their board connections,
noting their locations. Remove the cover plate and electronic board attached to it.
Loosen - but do not remove - the four socket head screws (3 mm) located on the PRT/cable pass
through plate. The plate is located on the inside of the base.
Slide the PRT out of the mounting post.
To reassemble continue as follows:
After reinserting the PRT into the mounting post and tightening the four socket head screws,
reassemble following the steps above in reverse order. Thermal grease may be applied lightly to the
PRT, if available. If the sensor lead locations were not noted correctly, follow Table 19.
Power up PG7000 and verify proper operation of all on-board sensors.
Table 19. PG7601 mounting post wire colors, description and location
WIRE COLORS DESCRIPTION AND LOCATION
Black/Yellow/White RPM (P4)
Black/Black/Black/Black Vacuum Sensor (center raised micro board)
White/White/Yellow/Yellow Mounting Post PRT (P2)
Purple/Blue/Red Motor Solenoid (J2)
Gray/Orange/Green/Brown LVDT (P1)