I.L. 40-385.5
11-1
11.1 COMMUNICATION ATTACHMENTS
An output is provided which will allow communica-
tions between the MDAR (REL-300) system and
external devices for data communications, network-
ing and remote setting. Two types of PONI (Product
Operated Network Interface) for interfacing are avail-
able depending on the application:
(a)
Interfacing by using an RS-232C-PONI allows
the MDAR (REL-300) communications to be
compatible with an IBM-PC.
(b)
Interfacing by using a INCOM
®1
-PONI permits
the MDAR (REL-300) to be addressable and to
share a local area network on a single wire pair
basis to make common use of a modem.
The PONI attachment is mounted on the backplate of
the outer chassis and connected to the backplane
module. It can be accessed from the rear panel.
An IBM XT or AT compatible computer, with a special
software “WRELCOM” provides for obtaining or
sending the setting information to the MDAR (REL-
300). It also can be used to monitor or change the
settings, 16 fault records, 16 intermediate target
records, oscillographic data and metering informa-
tion.
The MDAR (REL-300) front panel shows two fault
events (last and previous), but thru the remote com-
munication, 16 fault events and 16 record of interme-
diate target data can be obtained and stored.
For a remote setting, SETR should be set to YES;
then the settings can be changed remotely with a
user-defined password. If a user loses his assigned
password, a new password can be installed by turn-
ing the MDAR (REL-300) relay's dc power supply
“OFF” and then turn ON. MDAR (REL-300) allows a
change of password within the next 15 minutes, by
using a default PASSWORD. Refer to WRELCOM
manual for detailed information.
When in the remote mode, the computer can disable
1. “INCOM” is a registered trademark of the Westinghouse
Electric Corporation, Inc., which stands for INtegrated
COMmunications.
the local setting by showing SET = REM (in the
metering mode). Then, the setting cannot be
changed locally. In this situation, the only way to
change a setting locally would be to turn the dc
power OFF and
then ON. The computer will allow for a local setting
change within 15 minutes.
IMAC, an optional separate unit, stands for INCOM
Multi Access Controller, is a substation based com-
puter which can access the relays on the network,
automatically monitor relay status and provide
remote communication through a telephone modem.
It includes a CRT and printer.
11.2 16 FAULT RECORDS AND INTERMEDIATE
TARGETS.
The MDAR (REL-300) system saves the latest 16
fault records. The latest two fault records can be
accessed either via the front panel or via the commu-
nication port. The fault records 3 to 16 can only be
accessed via the communication port. On the front
panel, the “LAST FAULT” information is of the last
fault, the “PREVIOUS FAULT” information is of the
previous fault. These displays contain the target
information along with the “frozen” data at the second
cycle of the fault. When targets are available, the
LAST FAULT LED flashes. It flashes once per second
if only the LAST FAULT contains targets. It will flash
twice per second if 2 or more fault records are con-
tained.
The activation of fault data storage is controlled by
the selection of TRIP/Z2TR/Z2Z3 in the FDAT func-
tion, where
TRIP — start to store fault data only if trip
action occurs.
Z2TR — start to store fault data if Zone-2 unit
picks up or any trip action occurs.
Z2Z3 — start to store fault data if Zone-2 or
Zone-3 unit picks up or any trip action
occurs.
The fault records are stored in non-volatile memory
and are retained even if relay is deenergized. These
records can be deleted only by applying a rated volt-
Section 11. COMMUNICATION, FAULT DATA, INTERMEDIATE TARGET
AND OSCILLOGRAPHIC INFORMATION
