The VertX V1000 controller has two RS-485 serial buses with two ports each.
The two RS-485 serial buses are labeled P3 and P4. Each serial bus has a
10-pin connector divided into two ports, labeled Port 1 and Port 2 on the
P3 bus, and Port 3 and Port 4 on the P4 bus. Having two ports on
each bus provides the option of splitting each RS-485 bus into two physical connections,
allowing a total of four physical connections.The followings are the do's and don'ts.
- The interface modules must be connected to the RS-485 serial buses using the daisy chain
topology, not the star topology.
- Use only the "In" ports on the interface modules. This eliminates the possibility of
many interface modules dropping offline because one interface module died or lost
power.
- Terminate appropriately. The RS-485 serial bus expects a 120 Ω resistor to "terminate"
the ends of the loop. All the devices (including the V1000 controller) have jumpers for
this.
- The termination jumpers on the V1000 should be in the "Out" position if there are no
interface modules attached to the port. If there are interface modules attached, then the
termination jumper should be in the "In" position.
- All interface modules, except the ends of the serial chains, must have their termination
jumpers in the "Out" position.
- The dial on the interface module indicates its physical address (factory default=0) to
the controller it is attached to. Do not duplicate addresses on the same serial bus.
- It is recommended to wire the RS-485 to the position of the P9 terminal block of
the Vx00-series interface module. This is especially important when the RS-485
communication is in a "daisy chain" configuration. If the RS-485 is wired In and Out , and
power is lost, or the P9 terminal block is unplugged on a Vx00-series interface
module, RS-485 communications will be lost to downstream Vx00-series interface
modules.