The example below is a 2 bus system.
There is 1 Uplink card per BUS and 1 Master Panel (with DTC) per bus. From the diagram, the red CAT5 connecting the Uplinks together is the backbone bus. It is like a minibus of it’s own. And the backbone bus is the one that interconnects the GR2400 buses together.
On the picture below, I encircled each bus. As you can see, there are two GR2400 Bus's. The first one is BUS1, and the second one is BUS2. The one encircled on the left is your backbone bus. This includes the Server Card, and the Uplink Cards.
The way the system is connected is in a daisy chain manner. Each of our devices has 2 RJ-45 ports one cable going in and one cable going out.
So you start from one device with only one cable going out, going in to the next device and from that device going out to the next, so on and so forth. Until you reach the last device which will only have 1 cable going in.
In this manner, you will notice that the first and last device only has 1 cable connected to them. (DON’T LOOP THE SYSTEM BACK).
These end devices needs to be terminated.
In the exception of the UPLINK Cards. These cards has 2 sets of RJ-45 ports. One set for the GR2400 BUS, and the other set is for the BACKBONE bus.
This means that, if the Uplink is the last device on the GR2400 Bus and it is also the last device on the BACKBONE bus, the Uplink will have two terminators. One for each set… (the GR2400 side & the BACKBONE side).
1. The backbone bus is the connection between the uplink cards and the server card only.
2.The GR2400 Bus is the connection between the relay panels, switches, etc.
3. The uplink card is part of both the backbone bus, and the GR2400 bus that’s why it has 4 RJ-4 ports.
4. First and last device needs to have a terminator.