Setup, Network and Communication Manual ESTM / ESTM-L
17-88C1-*
11-88C1-7D0002
Notice
Technical data subject to change without notice.
No claims for damage arising from alternations, errors or misprints shall be allowed.
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4.8.3
Soft limiter
This function is available for firmware version 4.0.0 or higher.
Use of the Soft Limiter function as a limiter is not permitted for
ATEX
and
IECEx
applications
according
to
IEC/IEEE 60079-30-1.
Explosion protection is not ensured by this function.
Use hardware limiter of ESTM-L (SIL II) as limiter for ATEX
and IECEx applications according to IEC/IEEE 60079-30-1.
To activate the smart limiter set the Sensor Mode to
both
and
the Controller mode to
soft limiter
see also chapter 4.8.6
If the set temperature limit value (Set Point Soft Limiter) is
exceeded, the load relay or the load is switched off
permanently until a reset is done. This reset can be done by
the user or by means of the smart reset function.
Reset is possible if actual temperature (Actual Value Soft
Limiter) at the sensor 2 (TC2) is lower than the set point (Set
Point Soft Limiter) minus the set hysteresis (Hysteresis Soft
Limiter).
Sensor errors (wire breakage, short circuit, etc.) are detected
automatically. In the case of a sensor error, the load relay or
the load is switched off permanently until a reset is done by
the user.
Smart Limiter Reset
The Smart Reset function automatically resets the soft limiter
when the actual temperature (Actual Value Soft Limiter) at
the sensor 2 (TC2) is lower than the set point (Set Point Soft
Limiter) minus the set hysteresis (Hysteresis Soft Limiter) and
Smart Reset Status is active.
T-Off delay is the time that must have passed after the load
is switched off to enable the Smart Reset.
Remaining T-Off delay shows the remaining time until the
Smart Reset can be enabled.
The Smart Reset status
Enabled
means that the Remaining
T-Off delay time has expired or the load has been switched
off by the controller.
The smart reset status
Wait
means Wait until the Remaining
T-Off time has passed.
The Smart Reset status
Disabled
means that Smart Reset is
not possible because the load is switched on or the
Remaining T-Off delay time has not passed.
Function
Description
action / - effects on / valid values ranges
Soft Limiter Status
Status display Soft Limiter
ON/OFF
Set Point Soft Limiter
Temperature setpoint Soft Limiter
0-500°C
Actual Value Soft Limiter
Actual Value Soft Limiter
Hysteresis Soft Limiter
Hysteresis Soft Limiter
2-25K
Soft Limiter tripped
Switching Status Soft Limiter
Pre Alarm Soft Limiter
Pre Alarm Temperature Soft Limiter
0
– Soft Limiter Set point -2K
Reset
Reset Soft Limiter
Smart Reset Function
Smart Limiter Reset Function
ON/OFF
T-Off delay
Switch-off delay
300-3600 sec
Remaining T-Off delay
Remaining time Switch-off delay
Smart Reset Status
Smart Limiter Reset Status