Agromatic ESR-NK Series, Installation And Operating Manual, Page: 83 / 98

8 Maintenance and repair 8.2 Maintenance work
Actuators NK and VK, Position Controller ESR-NK 77
8.2.3 Leak test
Check the inside of the actuator every 6 months for humidity.
1. Loosen the fastening screws of the hood.
2. Remove the hood from the actuator.
3. Inspect the inside of the actuator and the hood for signs of humidity.
4. After the inspection and possibly required rectification, reinstall the hood
(see section
“5.8 Installing the hood”
).
Humidity inside the actuator may have the following causes:
−
Condensate
Condensate may be caused by varying ambient temperatures or tempera-
ture changes within the actuator (due to long motor run times).
If this is the case, install an anti-condensate heater in the actuator (see
section
“5.7 Anti-condensate heater (option)” ).
−
Damaged rubber sealing ring in the basic housing of the actuator
Return the actuator to Agromatic Regelungstechnik GmbH to have it re-
paired.
−
Leaking screwed cable glands/cable entries/filler plugs
Check whether the cable glands, cable entries or filler plugs are damaged
and whether the connection lines used have an outer diameter suitable for
the cable glands.
−
Replace any defective cable glands.
−
Only use connection lines with an outer diameter suitable for the cable
glands (see section “2.3.3 Protection classes of the actuator and the
stroke unit” ).
−
Damaged actuator housing or hood
−
Replace the damaged hood (see section “8.3 Spare parts” ).
−
If the actuator housing is damaged, return the actuator to Agromatic
Regelungstechnik GmbH to have it repaired.
−
Heater does not work
−
Have a qualified electrician inspect the heating resistor and the con-
nection lines of the heater for correct function.
−
Replace the damaged heater if required (see section “8.3 Spare
parts” ).