Siemens Reyrolle 7SR45 Argus Device Manual page 73

The thermal state may be reset from the fascia or externally via a binary input or through a remote command
from a control center.
Gn TauH
Default setting = 45.0 m
Setting parameter for 49 Heating Time Constant. Used during normal service conditions and overloads of a
protected equipment.
Gn Capacity Alarm
Default setting = Disabled
Selection to enable or disable 49 Capacity Alarm.
An alarm can be given if the thermal state exceeds a specified percentage of the thermal capacity setting of
the protected equipment. This can be used to warn the operator that a relay thermal trip will occur if this level
of protected equipment current continues. For the heating curve:
[fo_thermal-state_capacity-alarm, 1, en_US]
where θ = Thermal state at time t
I = Measured thermal current
I = Setting for 49 Overload function (or k ⋅ I
θ
The final steady-state thermal condition can be predicted for any steady-state value of input current where t
> τ.
Gn Capacity Alarm Setting
Default setting = 50 %
Setting parameter for 49 Capacity Alarm Setting.
Gn Stored Thermal Level
Default setting = Initial Level
Selection to select which last thermal level should be stored in the memory. If the stored thermal level is:
•
Initial Level (θ
•
Previous Level, then the relay shall store the actual thermal level in the memory. If the actual thermal
level θ ≥ 95 %, then θ = 95 % else θ actual shall be stored in the memory.
Gn Initial Thermal Level
Default setting = 0 %
Setting parameter to select the initial thermal level
Gn TauC
Default setting = 1.0 ⋅ TauH
Setting parameter for 49 Cooling Time Constant. This option shall be visible only in Dual Power variants.
The multiple of heating time constant takes into consideration the reduced rate of cooling of a protected
equipment. The function prevents the re-energizing of the electrical equipment until the equipment is cooled
based on the reclose inhibit binary output contact used in the circuit-breaker interlock.
Reyrolle, 7SR45, Device Manual
C53000-G7040-C101-2, Edition 09.2020
)
B
), then the relay shall always store θ
0
3.9 Thermal Overload Protection (49)
in the memory during trip or power off.
0
Functions
73