Thermal Overload Protection (ANSI 49)
57
7UM62 Manual
C53000-G1176-C149-3
the tripping signal via a binary input (”
”). Since the calculated
operating temperature may be higher than the maximum allowable operating
temperature after drop out of the binary input has taken place, the thermal overload
protection function features a programmable run-on time interval run-on time interval
(
) which is started when the binary input drops out. Tripping will be
defeated until this time interval elapses. The binary input used for emergency starting
affects only the tripping signal. There is no effect on the fault event protocol, nor does
the thermal memory reset.
Behaviour in the
Case of a Power
Supply Failure
For the overload protection, together with all other thermal protection functions of the
7UM62, you can set in the Power System Data 1 (parameter
ATEX100, see
Section 2.3) whether the calculated overtemperature will be buffered in case of a
power supply failure, or reset to zero. This second option is the default setting.
Figure 2-20 shows the logic diagram for thermal overload protection.
