Date Code 20070803
SEL Application Guide 2000-02
Application Guide
Volume II
AG2000-02
M
IRRORED
B
ITS
®
Communications
With FreeWave Technologies Spread
Spectrum Radios (Model FGR-115MB)
David Costello and Ken Fodero
I
NTRODUCTION
M
IRRORED
B
ITS
®
communications is an innovative technique that provides low-cost, high
performance communications directly between relays. The communications message contains
information to exchange internal logic directly between relays. Applications for M
IRRORED
B
ITS
include line protection pilot schemes, remote device control and monitoring, relay remote
tripping, automated sectionalizing and load restoration, bus protection, and much more.
Freewave FGR-115MB
Transceiver
NO. 1
(slave)
SEL-351S-7 Relay
(RXID=1, TXID=2)
SEL-351R Cabinet
FreeWave FGR-115MB
Transceiver
NO.1
(master)
Antenna
NO. 3
Surge Protection
NO. 7
RF Coaxial Cable
NO. 4
12 Vdc from Adapter
12 Vdc from SEL-351R
RF Coaxial Cable
NO. 4
Surge Protection
NO. 7
10 Miles, Line-of-Sight
Optical
Fiber
NO. 6
Antenna
NO. 3
SEL-351R-1
(RXID=2, TXID=1)
SEL-2815M (DTE)
NO. 5
SEL
-2
815M
(D
CE
)
NO
. 5
SEL-C285 Cable
NO. 2
SEL-351R Relay
(RXID=2, TXID=1)
Figure 1: Example Installation (Refer to Table 1)
SEL added a new protocol setting option, MB8, so that the M
IRRORED
B
ITS
message structure is
compatible with communication devices which require a specific character bit count, such as
point-to-point spread spectrum (900 MHz) radios.
