
Installation, Operation and Maintenance Manual
VCIOM-13254-EN Rev. 3
February 2021
43
Section 7: Troubleshooting
Troubleshooting
Section 7: Troubleshooting
!
WARNING
To prevent personal injury, the actuator must be in spring-return, Fail-safe Position and all
hydraulic pressure drained, including an optional accumulator, before opening any tube
lines or attempting replacement operations below.
Of all the system components, the actuator itself is least likely to malfunction and require
the most time and effort to service.
Table 8.
Troubleshooting
Symptoms
Possible Reason
EHO does not turn on
1. Ensure voltage is adequate to the unit.
2. Check to see that the electrical power is connected to the
correct terminals.
3. Branch circuit fuse blown out.
EHO is on, but motor does
not run
1. Ensure the Local/Off/Auto switch is in the proper position.
2. Ensure the field power wiring is an adequate size.
3. Power supply is insufficient.
4. Check to see if thermal overload is tripped.
EHO motor runs, but fails to
develop sufficient pressure
to open the valve
1. Low fluid level in reservoir.
2. Wrong motor shaft rotation.
3. Handpump isolation valve (O) is closed (if optional accumulator
is provided).
4. ESD solenoid is not energized because signal power is insufficient.
5. The Relief valve is cracking open. Check to ensure setting set to
factory setting.
EHO will not return to the
Fail-safe Position
1. Ensure the Local/Off/Auto switch is in the proper position when
initiating the open/close command.
2. Handpump isolation valve (O) is closed; preventing ability to
stroke to the Fail-safe Position.
Should any issue be experienced besides the symptoms noted above, please consult factory.
Important check points for automatic operation of the EHO:
1.
Ensure oil level is at the proper level.
2.
Ensure handpump isolation valve (O) is open.
3.
Check to see that the ESD (optional) signal power is on.