Manual 37353A
MFR 13 Packages - Protection Relay
Page 20/91
© Woodward
Chapter 4.
Functional Description
Control Inputs
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Blocking of protective
functions / Remote ac-
knowledgement
Terminal 5/6
Energizing this discrete input disables various protective functions. This
functionality may be desired if the control is used for generator protection.
This keeps the control from recognizing fault conditions (i.e. undervoltage,
underfrequency) when the generator is not operating. If blocking of these
protective functions is not required, the discrete input should not be con-
nected to any potential source.
The following protective functions cannot be blocked via this discrete
input:
•
Overvoltage
monitoring
•
Overfrequency monitoring
•
Zero voltage monitoring
•
Ground fault monitoring (calculated)
External acknowledgement
of the relays via the discrete
input "Blocking of protec-
tive functions / remote ac-
knowledgement"
External
Clearing ON
If the unit should not automatically reset the relays after the fault is no
longer present, the parameter "
Auto clearing Relays
" must first be
configured "
OFF
" (refer to "Auto Acknowledgement of the Relay" on
page 59).
OFF
..............Alarms that cannot be blocked will not automatically reset af-
ter the fault condition is no longer present. Pressing the
"Clear" button resets the relays.
ON
................All alarm messages are reset if terminals 5/6 ("Blocking of
protective functions / remote acknowledgement") are ener-
gized. Alarms that cannot be blocked are only reset after the
fault is no longer present.