Doosan heavy duty machine VBO calibration require you to do pump EPPR valve check,so here show you the steps.
Pump EPPR valve check
3.1. Measure the input & output current of the pump EPPR valve in certain condition
Ex. DX350LC-7, Normal outputs of pump EPPR valve (Please refer the shop manual to check the exact value
on each model)
- Not in operation: 300 ±30 mA
- Pilot operation: up to 750 ±30 mA
- Relief pressure up operation: 800 ±30 mA
3.2. Check the physical condition of the EPPR valve
3.2.1. Assembly condition
3.2.2. External damage
3.2.3. Short circuit
Ex. DX350LC-7(Please refer the shop manual to check the exact value on each model)
3.3. Measure the resistance of the EPPR valve
3.3.1. Measure the resistance of the valve coil: If the measurement is infinite, this indicates an
open circuit of the coil in the valve.
3.3.2. Measure the resistance of the valve coil: If the measurement is 0Ω, this indicates a short
circuit of the coil in the valve.
More topics for Doosan,please refer to:Doosan Trouble Repair