DS 350 G Boom Control Troubleshooting- TMS/TTS870 / RT865 BXL
031-300-190-039 Rev. B 4/30/99
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Auto mode / Manual mode:
The operator selects auto mode or manual mode using the rocker switch in the dash board.
Auto mode is the working mode and manual mode is used for rigging or sequencing purpose
only.
Pilot pressure switch signal / Analog output signal:
Two pressure switches in the pilot pressure circuit are used to distinguish between boom
extend or boom retract. The two circuits are wired through the crane interface connector into
the DS 350 G central unit.
When the operator extends the boom, the pressure switch signal at central unit terminal
A101-X1/38 changes from 0V to +24V. The boom control logic allows electrical current to
flow to the extend pressure reducing valve coil. The minimum current equals 0 mA with the
control in neutral position. The maximum current output equals 800 mA.
To measure the coil current while extending, remove wire #20from central unit terminal
A101-X1/63. Connect the Amp-meter in series with wire #20 to terminal X1/63.
When the operator retracts the boom, the pressure switch signal at central unit terminal
A101-X1/40 changes from 0V to +24V. The boom control logic allows electrical current to
flow to the retract pressure reducing valve coil. The minimum current equals 0 mA with the
control in neutral position. The maximum current output equals 800 mA.
To measure the coil current while retracting, remove wire #21 from central unit terminal
A101-X1/64. Connect the Amp-meter in series with wire #21 to terminal X1/64.