Here comes the instruction show how to do Doosan machine VBO calibration Joystick check.
1.1. Measure the input & output voltage of the joystick pressure sensor
1.1.1 Check if the output voltage is 1V when it is connected under unloaded condition.
1.1.2 Check if the output voltage of the pilot pressure sensor while the machine is in operation.
(Take the DMS-5 monitoring data during the test)
1.1.3 Check if the voltage value measured at the pressure sensor is matched with the pressure
indicated on the gauge panel.
1.1.4 Operate the machine and check if the pressure value indicated on the gauge panel is
changed according to changes in the pressure.
Ex. DX350LC-7 Pilot pressure sensor (Please refer the shop manual to check the exact value on each model)
* Operating voltage: 24 V ±10%, Output voltage: 1 ~ 5 V, Operating current: max. 20 mA,
Measuring pressure: 0 to 50 bar, Measurement tolerance: ±3%
*Formula for voltage-pressure conversion: Voltage = (0.08 x Pressure) + 1
1.2. Check the physical condition of the pressure sensor
1.2.1. Assembly condition
1.2.2. External damage
1.2.3. Short circuit
Ex. DX350LC-7, Boom up pressure sensor (PT-1)
1.3. Proceed with air bleeding on the pilot line
1.3.1. Minimum RPM required
1.3.2. Select the location closest to MCV for releasing the pilot line
Ex. DX350LC-7 Boom down (Please refer the shop manual to check the exact position on each model)
1.3.3. Pilot hose in a relation with calibration fail should be slightly open in order that it should
allow only air to escape and hydraulic pressure to escape to a minimum.
1.3.4. Prevent the contamination of the machine and floor by leaking oil