IEC15000022 V1 EN-US
It is possible to power-cycle the IED in this state without losing the forcing
states and values. This means that once a signal is forced, and the IED remains
in IED test mode, the input or output will appear “frozen” at the value selected
by the user, even if the IED is switched off and back on again.
Freezing a signal value without changing it
GUID-FD76AAC1-7098-47D3-A3A1-6ACDF509ED91 v1
•
Set the status of a signal to Forced, in the forcing menu that corresponds to the I/O card
in question. See example of LHMI menu in figure
IEC15000020 V1 EN-US
Figure 32: Example of LHMI menu using BIM3
The signal “freezes” and will not change value even if, for example, a binary input signal voltage
changes level, or if a binary output is activated as the result of a protection function block
activating.
11.8.3.2
Forcing by using PCM600
GUID-E9D0DAE6-7A86-4FF9-943E-42039015D05B v1
In PCM600 the concept is a bit different compared to LHMI. The forcing is accomplished by
entering a forcing session. Within such a session, multiple signals on multiple I/O boards may
be edited and changed at the same time and has no effect on the IED. Once the user is
satisfied with the forcing setup, then all the changes can be effectuated simultaneously
towards the IED, potentially changing inputs and outputs on multiple I/O boards at the same
time. It is also possible to abort this operation (described in step 6 below) and to
Section 11
1MRK 502 067-UEN B
Testing IED operation
92
Commissioning manual