
HQ-004 Quarter-turn Electric Actuator 
Installation Operation& Maintenance Manual 
Doc No. : HumG-HQ004-21 Rev0  Page  8 / 9  Valve Automation Leader, HKC 
WARNING:  
Treat cover with care. Gap surfaces must not be damaged or dirtied in any way. 
Do not jam the cover during fitting. 
6.2. Tools 
6.2.1. Metric Allen Key (Hex Wrench) × 1 
6.2.2. Screw Driver × 1 
6.2.3. Metric Spanner × 1 
6.2.4. Wrench 200mm × 1 
6.2.5. Wrench 300mm × 1 
6.2.6. Wire Stripper Long Nose × 1 
6.2.7. Multi-meter (Ac, Dc, Resistance) × 1 
 
7. Trouble Shooting 
The following instructions are listed in the order of the most common difficulties encountered during 
the installation and start-up. 
7.1. The actuator does not respond 
7.1.1. Visually inspect the actuator to check no shipping or handling damage has occurred 
7.1.2. Verify the line voltage supplied to the actuator; check that the line voltage matches with 
the rating on the actuator’s nameplate 
7.1.3. Check the internal wiring against the supplied wiring diagram of the actuator 
7.1.4. Check the limit switch cams 
7.2. The actuator is supplied with power but does not operate 
7.2.1. Verify the line voltage supplied to the actuator; check that the line voltage matches with 
the rating on the actuator’s nameplate. 
7.2.2. Check that the actuator torque is greater than the valve torque 
7.2.3. Check the limit switch cams 
7.2.4. Check that the torque switches have not been tripped 
7.2.5. Check the mechanical travel stop adjustment 
7.2.6. Verify  that  the  actuator  against  the  rotation  of  the  valve  (standard  units  are  counter-
clockwise rotation to open) 
7.2.7. Check for any corrosion and condensation that any of the electrical or mechanical devices 
have not been contaminated 
7.2.8. Verify that coupler/bracket is correctly installed and is not causing any binding 
7.3. Actuator runs erratically 
7.3.1. Check the ambient temperature 
7.3.2. Verify that the duty cycle has not been exceeded 
7.3.3. Check the position of manual override lever 
 
Motor will not run 
Open in control circuit  Refer  to  appropriate  wiring  diagram  and 
check for continuity 
Insulation  resistance  breakdown 
in motor  Perform megger Test 
No power available to actuator
Tripped circuit breaker  Reset circuit breaker 
Manual Override Nut hard to 
turn 
Valve stem improperly lubricated
Lubricate with grease 
Clean out old grease and replace with 
recommended lubricant
Actuator  lubrication  has  broken 
down 
Valve packing gland too tight  Loosen packing gland nuts as necessary 
Jammed valve  Refer to valve maintenance 
Valve only opens or closes 
partially with motor  Limit switch improperly set  Check setting and reset if necessary 
Manual Override Nut will not 
operate valve 
Stripped gearing  Replace as necessary 
Broken hand wheel shaft  Replace as necessary 
Broken valve stem  Repair or replace as necessary 
Motor runs but will not operate 
valve  Stripped gearing  Replace as necessary