Description Of Signals; In The Event Of Valve Malfunction - YUKEN KOGYO ELDFG-01EH 10 Series Instruction Manual

5.4 Description of signals

5.4.1 Input signal and spool travel monitoring
Input signals to drive the valve are used for spool position control.
The types of input and spool travel monitoring signals differ depending on the model
number.
Model Number
ELDFG-*EH-*-D
ELDFG-*EH-*-E
ELDFG-*EH-*-F
* For the 4 - 20 mA type, an input signal of 1.5 mA or less means that the spool is in its
neutral position (12 mA).
Input (+)
Input Signal
Input (-)
Spool Travel Monitoring

5.5 In the event of valve malfunction

In the event of valve malfunction, check the following items.
(1) When the power indicator LED (green) does not light up:
- Check the power supply voltage.
→ Check the power supply side if no voltage is present.
(2) When the deviation alarm LED (red) lights up:
- The spool has malfunctioned.
→ Spool sticking or seizure caused by foreign matter in the hydraulic fluid.
(3) When the valve spool travel (monitored voltage) does not change in response to the
command input
- Check the command signal input.
→ Check the input signal and valve model (input type).
- Check the wiring.
→ Check that each cable has been connected correctly.
- Check the power supply voltage.
→ Check the power supply side if the voltage is low.
Input Signal
4 - 20 mA
Ｄ
E
F
C
ELDFG-*EH-*-E/F
Current Output:
Spool Travel Monitoring
±10 V
*
±10 mV
ELDFG-*EH-*-E/F
Valve
Current Input:
- 17 -
EM-1359
±10 V
4 - 20 mA
±10 mV
/E＊/F＊