21/07/2010
11
MRAR 01/96 C
4.3.1 Password programming
The
MRAR
relay is normally delivered with the preset password "
∧∧∧∧
", it can be reprogrammed
using the removable code jumper J1. After power on and the pressing of any push button, the
MRNS
relay enquires for a new password with the text
<PSW?>
appearing on the display. A new password is
then entered by pressing a combination of
<SELECT>, <UP>, <DOWN>
or
<ENTER>,
as chosen by
the user. After the new password has been given, the relay module is extracted from its case and code
jumper J1 removed.
4.3.2 Alarm and Trip relay function
The following functions of the
MRAR
alarm relays may be preset using jumpers J1 & J2:
•
•
•
•
Alarm relay activation upon initiation or after a trip
•
•
•
•
Manual or Automatic reset of the output relays
Code jumper J2 - OFF
The alarm relays respond directly upon the initiation of the corresponding measuring circuit. Thus,
an alarm signal, e.g. for negative sequence current, will be given before the relay trips.
Code jumper J2 - ON
The alarm relay responds only after the relay has tripped. Thus, the alarm relay and the trip relay
respond at the same time.
Code jumper J3 - OFF
All output relays will be reset automatically after tripping, once the fault has been cleared.
Code jumper J3 - ON
All output relays remain activated and must be reset manually by pressing the
<RESET>
push
button, after the fault has been cleared.
Summarising the coding possibilities
Code jumper
Function
Code jumper Position
Operation Mode
J1
Password
OFF
ON
Normal position
Password programming
J2
Fast Trip
OFF
ON
Fast Trip before the First
Reclose
Fast Trip after last
Reclose.
J3
Reset
OFF
ON
Output relays will be reset
automatically.
Output relays will be reset
manually.
