Corrective Actions; Faults During Operation/Commissioning; Motor Protection (Thermal Monitoring) - AUMA SQEx 05.2 Manual

12 Corrective actions

12.1 Faults during operation/commissioning

Table 20: Faults during operation and commissioning
Fault
Mechanical position indicator cannot
be set.
In spite of correct setting of mechani-
cal limit switching, actuator operates
into the valve or actuator end position.
No value can be measured at measur-
ing points of the RWG.
Measuring range 0/4 – 20 mA or maxi-
mum value 20 mA at position transmit-
ter cannot be set or supplies an incor-
rect value.
The measuring range 0/4 – 20 mA at
EWG position transmitter cannot be
set.
Limit and/or torque switches do not
trip.
Handwheel rotates on the shaft with-
out transmitting torque.
Switch check The red test buttons [1] and [2] are used for manual operation of the switches:

12.2 Motor protection (thermal monitoring)

Possible causes Overload, running time exceeded, max. number of starts exceeded, ambient tempera-
Description/cause
Reduction gearing is not suitable for actuator
swing angle.
The overrun was not considered when setting the
limit switches.
The overrun is generated by the inertia of both the
actuator and the valve and the delay time of the
actuator controls.
Current loop across RWG is open.
(Position feedback 0/4 – 20 mA is only possible if
the current loop is closed across the RWG.)
Reduction gearing is not suitable for actuator
swing angle.
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.
Switches are defective or switch setting is incor-
rect.
Actuator in version with overload protection for
manual operation: Shear pin rupture due to exces-
sive torque at handwheel.
Figure 37: Test buttons
[1]
1. Turn test button [1] in direction of the TSC arrow: Torque switch CLOSED trips.
2. Turn test button [2] in direction of the TSO arrow: Torque switch OPEN trips.
If the actuator is equipped with DUO limit switches (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.
Thermal switches are provided in the motor winding to monitor the motor winding tem-
perature. The thermal switches trip as soon as the max. permissible winding tempera-
ture has been reached.
ture exceeded.
Remedy
Set gear stage of the reduction gearing.
• Determine overrun: Overrun = travel covered
from switching off until complete standstill.
• Set limit switches again considering the over-
run. (Turn handwheel back by the amount of
the overrun)
• Connect link across RWG to XK (terminals
23/24)
• Connect external load to XK, e.g. remote indi-
cation.
• Observe max. load R .
B
Set gear stage of the reduction gearing.
Request AUMA Service.
Check setting, if required, reset end positions.
Refer to Switch check [} 39], replace switches if
required.
Dismount handwheel. Replace overload protection
and remount handwheel.
Corrective actions
[2]
39