Teagle Tomahawk 808S, Инструкция / Перечень запасных частей

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SECTION 9. SOLENOID VALVE AND CONTROLS REPAIR
AND ADJUSTMENT
9.1 Checking coils for correct operation
Without the tractor engine running it is usually possible to hear the click of cartridge valves moving when the
switches are operated.
Remove the coil from the cartridge valve by unscrewing the retaining nut being careful not to lose the ’O’ ring
behind the nut. With the switch on the control box operated, the magnetic effect of the coil should be detectable
on a screwdriver placed inside the coil.
If the magnetic effect cannot be detected try a different coil attached to the same lead or alternatively check for a
switched current on the lead with a multimeter. If there is no switched electrical current at the coil connector it
may be a fault in the wiring, switch or connector on the cab control box which can only be traced with the aid of a
multimeter/test lamp.
9.2 Removal of the proportional cartridge
Remove the coil from the proportional cartridge valve by unscrewing the retaining nut being careful not to lose the
’O’ ring behind the nut.
Removal of the cartridge is best effected with the use of tool HYD5336 which allows the cartridge to be removed
by a 1” AF deep socket. Where the tool HYD5336 is not available then adjacent components may have to be
removed to obtain access with a 9/16” AF open ended spanner.
Reattach the proportional coil to the cartridge and operate through the bed chain speed control range. A variable
opening of the cartridge should be noted.
9.3 Diagnosing bed chain electronic circuit for faults
Diagnostics can only be achieved with the use of a multimeter capable of measuring a variable voltage in the
range 0-12v.
9.3a Small domed button controls
As the potentiometer speed control on the control box is varied from stop to full flow it should be possible to
measure the following voltages on the connector in the middle of the junction box circuit board, cable labelled 3
(12v), 4 (5v), 5 (0v) & 6 (variable 0 to 5v). If only the variable voltage has failed then the potentiometer in the cab
control box may have a faulty connection or has failed. Check for good connections, if none are apparent refer the
control box to Teagle Machinery Ltd for repair.
Measure the varying voltage at the connector to the coil with a multimeter, a variation of 6v in a range from 4v to
10v should be measured. If the above satisfactory readings cannot be obtained then one of the two following
faults has occurred:
1. Bed chain max and min values need adjustment usually indicated by a variable voltage outside the given
range.
2. Flow control circuit board failed - Replace junction box circuit board. (Section 9.4)
9.3b Large flat button controls
Measure the varying voltage at the connector to the coil, a variation of 6v in a range from 4v to 10v should be
measured. If the above satisfactory readings cannot be obtained then one of the two following faults has occurred:
1. Bed chain max and min values need adjustment usually indicated by a variable voltage outside the given
range.
2. Control box potentiometer or circuit board has failed - refer the control box to Teagle Machinery Ltd for
repair.
3.
Note: Control boxes are available on an exchange basis to prevent any unnecessary down time.
9.4 Replacing junction box circuit board
Remove the circuit board in the junction box by releasing all of the wires from the electrical connector blocks
noting the positions of the solenoid wires. Unscrew the circuit board retaining screws and remove the circuit
board. Refit the new circuit board ensuring that all wires are returned to their original positions and adjust the I
Min and I Max settings (Section 9.11) to ensure correct bed chain speed variation.