10.2.
Motor protection monitoring (thermal monitoring)
In order to protect against overheating and impermissibly high surface temperatures
at the actuator, PTC thermistors or thermoswitches are embedded in the motor
winding. Motor protection trips as soon as the max. permissible winding temperature
has been reached.
The actuator is switched off and the following fault signals are issued:
●
LED 3 (factory setting: motor protection tripped) on the local controls is illumin-
ated.
●
Status indications
S0007 Fault
or
S0011 Failure
display a fault.
The fault
Details
is displayed when selecting
Thermal fault
.
The motor has to cool down before the operation can be resumed.
Depending on the parameter setting (motor protection behaviour), the fault signal is
either automatically reset or the fault signal has to be acknowledged manually.
Manual acknowledgement can be made:
●
In selector switch position Local control (LOCAL) via push button RESET.
●
In selector switch position Remote control (REMOTE):
-
Via fieldbus, Reset command, byte 1 bit 3 of output data if fieldbus is the
active command source.
-
Or via a digital input (I/O interface) with RESET command if a digital input
is configured for
RESET
signal and the I/O interface is the active command
source.
In addition, the actuator controls cyclically (once per month) check the motor
protection monitoring for its proper function. If this check fails, the actuator controls
generate the fault indication:
IE mot. prot. monitor
Motor protection behaviour
Required user level:
AUMA (6)
.
Device configuration M0053
Actuator M0168
Motor prot. mode M0169
Default values:
Non-explosion-proof actuators =
Auto
Explosion-proof actuators =
Reset
Setting values:
Auto
Automatic reset after the motor has cooled down.
Not possible for explosion-proof version.
Reset
Manual reset.
Once the motor has cooled down, the fault has to be acknowledged (reset) manually
as described above.
If required the thermal overload relay has to be reset manually. To this end, remove
the cover on the back of actuator controls and operate the reset button on the thermal
overload relay.
10.3.
Type of duty monitoring (motor starts and running time)
This function monitors the permissible type of duty (e.g. S2 - 15 min) of the actuator.
For this, actuator controls monitor possible excess of
●
Permissible motor starts (cycles) per hour
●
Permissible running time (on-time) per hour
If any of these values has been exceeded, the actuator will however not be stopped,
but the following warning signals are issued.
107
Actuator controls
ACV 01.2/ACVExC 01.2 Profibus DP
Monitoring functions