TD_MRN3-3_08.06_GB
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5.7 Additional
functions
5.7.1 Setting procedure for blocking of
the protection functions and
assignment of output relays
The blocking function of the
MRN3-3
can be set ac-
cording to requirement. By applying the aux. voltage
to D8/E8, the functions chosen by the user are
blocked. Setting of the parameter should be done as
follows:
•
When pressing push buttons <ENTER> and <TRIP>
at the same time, message "BLOC" is displayed (i.e.
the respective function is blocked) or "NO_B" (i.e.
the respective function is not blocked). The LED allo-
cated to the first protection function Char1 lights
green.
•
By pressing push buttons <+> <-> the value dis-
played can be changed.
•
The changed value is stored by pressing <ENTER>
and entering the password.
•
By pressing the <SELECT/RESET> push button, any
further protection function which can be blocked is
displayed.
•
Thereafter the menu is left by pressing
<SELECT/RESET> again.
•
If the <SELECT/RESET> key is actuated again, the
blocking menu is left and the assignment mode is
accessed.
Function Description
Display LED
Char1 Undervoltage
step
1
BLOC green
Char2 Undervoltage
step
2
BLOC green
U1 Voltage
step
1 BLOC
green
U2 Voltage
step
2 NO_B
green
U3 Voltage
step
3 NO_B
green
f1 Frequency
step
1
BLOC
green
f2 Frequency
step
2
BLOC
green
f3 Frequency
step
3
NO_B
green
∆Θ
Vector surge
BLOC
green
df/dt
Frequency changing
rate
BLOC green
Table 5.3: Blocking function for two parameter sets
Assignment of the output relays:
Unit
MRN3-3
has five output relays. The fifth output re-
lay is provided as permanent alarm relay for self su-
pervision and it is normally on. Output relays 1 - 4 are
normally off and can be assigned as alarm or tripping
relays to the protection functions which can either be
done by using the push buttons on the front plate or
via serial interface RS485. The assignment of the out-
put relays is similar to the setting of parameters, how-
ever, only in the assignment mode.
The assignment mode can be reached only via the
blocking mode.
By pressing push button <SELECT/RESET> in blocking
mode again, the assignment mode is selected.
The LEDs Char1, Char2, U1, U2, U3, f1, f2, f3 and
∆Θ
/df light up
green
when the output relays are as-
signed as
alarm relays
and LED t>
red
as
tripping re-
lays
.
Definition:
Alarm relays
are activated at pickup.
Tripping relays
are only activated after elapse of the
tripping delay.
After the assignment mode has been activated, first
LED Char1 lights up green. Now one or several of the
four output relays can be assigned to under voltage
characteristic 1 as alarm relays. At the same time the
selected alarm relays for under voltage characteristic 1
are indicated on the display. Indication "1_ _ _"
means that output relay 1 is assigned to this step.
When the display shows "_ _ _ _", no alarm relay is
assigned to this under voltage element. The assign-
ment of output relays 1 - 4 to the current elements can
be changed by pressing <+> and <-> push buttons.
The selected assignment can be stored by pressing
push button <ENTER> and subsequent entry of the
password. By pressing push button <SELECT/RESET>,
LED Char1 lights up green and t> lights up red. The
output relays can now be assigned to this element as
tripping relays.
Relays 1 - 4 are selected in the same way as de-
scribed before. By repeatedly pressing of the
<SELECT/RESET> push button and assignment of the
relays all elements can be assigned separately to the
relays. The assignment mode can be terminated at any
time by pressing the <SELECT/RESET> push button for
some time (approx. 3 s).
Note:
•
The function of jumper J2 described in general de-
scription "MR Digital Multifunctional Relays" does not
apply for
MRN3-3
. For relays without assignment
mode this jumper is used for parameter setting of
alarm relays (activation at pickup or tripping).
A form is attached to this description where the setting
requested by the customer can be filled-in. This form is
prepared for telefax transmission and can be used for
your own reference as well as for telephone queries.
