10.
Corrective action
10.1.
Faults during commissioning
Table 8: Faults during commissioning
Remedy
Description/cause
Fault
Exchange reduction gearing.
Reduction gearing is not suitable for
turns/stroke of the actuator.
Mechanical position indicator
cannot be set.
●
Determine overrun: Overrun = travel
covered from switching off until complete
standstill.
●
Set limit switching again considering the
overrun (turn handwheel back by the
amount of the overrun).
The overrun was not considered when setting
the limit switching.
The overrun is generated by the inertia of
both the actuator and the valve and the delay
time of the controls.
In spite of correct setting of limit
switching, actuator operated into
the valve end position.
●
Connect link across RWG to XK (terminals
23/24)
●
Connect external load to XK, e.g. remote
indication.
●
Observe maximum load R
B
.
Current loop across RWG is open.
(Position feedback 0/4 – 20 mA is only pos-
sible if the current loop is closed across the
RWG.)
No value can be measured at
measuring points of the RWG.
Exchange reduction gearing.
Reduction gearing is not suitable for
turns/stroke of the actuator.
Measuring range 0/4 – 20 mA or
maximum value 20 mA at position
transmitter cannot be set or sup-
plies an incorrect value.
Call AUMA service.
The LED on the EWG either flashes in setting
mode a) single flash or b) triple flash:
a) EWG is not calibrated.
b) Magnet positions of EWG are not aligned.
The measuring range 0/4 – 20
mA at EWG position transmitter
cannot be set.
●
Check setting, if required, reset end posi-
tions.
●
Refer to <Check switches> and replace
the switches if required.
Switch is defective or switch setting is incor-
rect.
Limit and/or torque switches do
not trip.
Switch check
The red test buttons [1] and [2] are used for manual operation of the switches:
1.
Turn test button [1] in direction of the TSC arrow: Torque switch CLOSED trips.
3.
Turn test button [2] in direction of the TSO arrow: Torque switch OPEN trips.
If the actuator is equipped with a DUO limit switching (option), the intermediate
position switches (LSA and LSB) will be operated at the same time as the torque
switches.
1.
Turn test button [1] in direction of the LSC arrow: Limit switch CLOSED trips.
2.
Turn test button [2] in direction of the LSO arrow: Limit switch OPEN trips.
10.2.
Motor protection (thermal monitoring)
In order to protect against overheating and impermissibly high temperatures at the
actuator, PTC thermistors or thermoswitches are embedded in the motor winding.
They trip as soon as the max. permissible winding temperature has been reached.
34
SQ 05.2 – SQ 14.2/SQR 05.2 – SQR 14.2
Corrective action
