PAT DS 150, Service Manual

Page: 23 / 55

Drawings 16
4.6 Central Unit Board Layout And Measuring Points 024-150-300-001
5 PROCEDURE
EPROM replacement in Central Unit
Follow this procedure when changing EPROM’s in the DS150 central units.
1. Remove cover, from central unit.
CAUTION:
Before handling the EPROM, discharge any static electricity from your body by
touching a ground source. The EPROM could be damaged if this procedure is not followed.
Use the central unit main board layout and measuring point drawing to locate the system and data
EPROM‟s.
2. Remove the old EPROM from the main board using an EPROM puller. Be careful not to bend the
legs of the EPROM when removing it.
3. Installing the new EPROM:
 Ensure the notch is in the correct direction. The direction of the EPROM is determined by the notch
on the end of the EPROM.
 The DATA and TLK EPROM’s fill the bottom of the socket as shown by the arrows.
 Place EPROM in the correct EPROM socket as shown.
4. Inspect gasket and install cover using the following procedures to prevent any moisture from
entering the central unit.
Reference material:
031-300-340-002 Central Unit Cover Installation and Tightening Procedure; Rev A.
031-300-340-003 Central Unit Gasket Recommendations; Rev -.
Piston & Rod Pressure Channel Zero Point Adjustment
Use the central unit main board layout and measuring point drawing to make the following
adjustments.
1.
Lower boom all the way down (no rest pressure) then disconnect hydraulic hose from the
piston side pressure transducer.
2. Connect a digital voltmeter to main board
A) black (-) lead to mp10
B) red (+) lead to mp11
3. Adjust P1 to obtain a reading of 0.500 volts (500mv) on meter.
4. Disconnect hydraulic hose from the rod side pressure transducer.
5. Connect a digital voltmeter to main board
A) BLACK (-) lead to MP10
B) RED (+) lead to MP12
6. Adjust P2 to obtain a reading of 0.500 volts (500mv) on meter.
7. Reconnect hydraulic hoses to pressure transducers, and then bleed the air from hydraulic lines
.