RELAY DRIVER
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5.2 Communications Wiring
The Relay Driver communicates through both the RS-232
serial port and Meter Bus ports. The serial port allows
communication with the Relay Driver using a PC while the
Meter Bus allows communication between the Relay Driver and
other Morningstar Devices. Morningstar Devices include the
TriStar controller, local and remote TriStar Meters, and of
course the Relay Driver.
5.2.1 Meter Bus Network
A Meter Bus network consists of two (2) or more Morningstar
devices daisy-chained together with RJ-11 cables. The Meter
Bus network uses a proprietary communication protocol to
transmit and receive information between each Morningstar
Device on the network.
The Meter Bus ports on the Relay Driver are opto-isolated and
do not provide power to the Meter Bus. Isolation allows each
Relay Driver on the Meter Bus network to have its own power
source and ground if needed.
However, every Meter Bus network must have power. The
TriStar Controller provides the needed power to the Meter Bus
so that communication is possible. For this reason, every Meter
Bus network must have a TriStar controller (other future
Morningstar Devices may also provide Meter Bus power)
An example Meter Bus network is shown in Figure 25. A
TriStar controller provides power to the Meter Bus network.
Two (2) DIN rail mounted Relay Drivers and a TriStar Remote
Summary of Contents for RelayDriver
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