HBC-4301 Operators Manual - Novatech Controls

8.4 Operating with two control cases
8.4.1 Connecting the cases
The computer must be connected to one of the HBC-4301 control cases. Use the connector
labelled COMPUTER on the control case and the USB adapter connected to the computer.
If the HBC-4301 was purchased as a single control case an RS232 communications lead will
have been supplied. When a second control case is to be networked to the first case the
following changes must be made –
1. The computer must have an RS485 communications port. Do not make an RS485 port
by using a USB port to an RS232 port and then another adapter to make the RS485
port. The only 2 options are -
If the PC has a true hardware RS232 port, then an RS232 to RS485 adapter can
be used.
If the PC only has USB ports then use a USB to RS485 adapter.
2. An RS485 network cable must be used instead of the RS232 lead from the PC to the
first control case.
3. A Novatech network cable must be used between the two cases.
4. Both control cases must have their internal communications link set to RS485. This
link is found on the Main PCB, under the shield in the base chassis of the control case.
5. Remove LK3 located beside the RS232/RS485 link on the main PCB.
NOTE:
The RS485 communications cable can still be used with a single HBC-4301.
i.e. After this link has been set to RS485 it does not need to be changed back to RS232 as
long as the RS485 cable is available.
The two HBC-4301 control cases can be connected together using either of the connectors
labelled NETWORK.
For details of the wiring connections see chapter 18.1, External wiring.
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