22
TB MRU3-2 12.00 E
5.9
Additional functions
5.9.1
Setting procedure for blocking the
protection functions
The blocking function of the
MRU3-2
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 U< lights red.
•
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
U<
Undervoltage step 1
BLOC
green
U<<
Undervoltage step 2
BLOC
green
U>
Overvoltage step 1
NO_B
green
U>>
Overvoltage step 2
NO_B
green
U1<
Undervoltage step in
positive-phase
sequence system
BLOC
green
U1>
Overvoltage step in
positive-phase
sequence system
BLOC
green
U2>
Overvoltage step in
negative-phase
sequence system
BLOC
green
U0>
Overvoltage step in
zero-phase sequence
system
BLOC
green
Table 5.5: Blocking function for two parameter sets
Assignment of the output relays:
Unit
MRU3-2
has five output relays. The fifth output re-
lay is provided as permanent alarm relay for self su-
pervision is normally on. Output relays 1 - 4 are nor-
mally off and can be assigned as alarm or tripping re-
lays to the voltage functions which can either be done
by using the push buttons on the front plate or via se-
rial interface RS485.
The assignment of the output relays is similar to the set-
ting of parameters, however, 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 relays are assigned as follows: LEDs U<, U<<,
U>, U>>, U1>, U1<, U2> and U0>are two-coloured
and light up
green
when the output relays are as-
signed as
alarm relays
and t
U<
, t
U<<
, t
U>
, t
U>>
, t
U1<
, t
U1>
,
t
U2>
, and t
U0>
.
red
as
tripping relays
.
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 U< lights up green. Now one or several of the
four output relays can be assigned to under voltage
element U< as alarm relays. At the same time the se-
lected alarm relays for under voltage element 1 are
indicated on the display. Indication "1_ _ _" means
that output relay 1 is assigned to this under voltage
element. When the display shows "_ _ _ _", no alarm
relay is assigned to this under voltage element. The as-
signment of output relays 1 - 4 to the current elements
can be changed by pressing <+> and <-> push but-
tons. The selected assignment can be stored by press-
ing push button <ENTER> and subsequent input of the
password. By pressing push button <SELECT/RESET>,
LED U< lights up red. The output relays can now be
assigned to this voltage 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 (abt. 3 s).
Note:
•
The function of jumper J2 described in general de-
scription "MR Digital Multifunctional Relays" does
not apply for
MRU3-2
. For relays without assign-
ment 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.
