21/07/2010
5
MRAR 01/96 C
2. Application
In transmission line networks about 70% of the occuring failures are transient; arcing, tree branches on
power lines etc. With the use of auto-reclosing techniques it is possible to "switch off" the supply until
these faults have been removed. Without utilzing auto-reclosing techniques, consumer interuptions
occur frequently which is unfortunate especially as the vast majority of faults have been removed a short
time after the initial outage.
The
MRAR
digital auto-closing relay is a universal device suitable for a number of reclosing schemes.
A very wide range of applications may be encompassed when the MRAR is combined with other relays
from the MR range (eg. the MRI-I & MRCS).
The protective functions of the
MRAR
are summarised as follows:
•
Independent adjustable time ranges.
•
Four digit counter for display of the completed auto-reclosing.
•
High-Set blocking output available
•
External blocking and release.
•
Suitable for use with a number of IDMT devices.
•
Maintenance Alarm and Lock-out.
•
Suitable for generator and similar applications requiring a check-sync function.
3. Features and characteristics
•
Complete digital processing of all logic inputs
•
Extremely wide setting ranges with fine setting steps
•
Unauthorised user access control through password protection
•
User defined password
•
Continuous self-supervision of software and hardware
•
Outstanding design flexibility for easy selection of appropriate operational scheme for
numerous applications
•
Serial data communication facilities via RS485
•
Wide voltage range for DC or AC power supply
•
Withdrawable modules
