OPTO 22 G4LC32, User Manual

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G4LC32 User’s Guide
COMMUNICATION SWITCHES
Important: Do not try to use RS-232 and RS-422/485 communications mode simultaneously on one COM port.
Unreliable communications will result.
RS-422/485 Switch Settings
The switches for terminating the G4LC32 RS-422/485 communications lines are located inside the unit, just behind
the front panel.
The controller has provisions for two-wire or four-wire communications. Two-wire communications is half duplex,
where the transmitter is always off unless a message is being sent. When the transmitter is ON, the receiver is
turned OFF and vise versa. Four-wire allows for full-duplex transmission.
Select two-wire or four-wire communications, then select terminated or not terminated. Termination is only needed
when the G4LC32 is at the physical beginning or end of the transmission line.
The following diagram shows how to set the switches for each of the four possible switch configurations.
RS-422/485 Communication Switch Setting
RS-232 Switch Settings
If you are using the ports for RS-232 communication, the respective RS-422/485 switch must be in the 4-wire
terminated position . The ports may be used for either RS-232 or RS-422/485 communication, but not both at the
same time.
IRQ Switch Settings
There are no switches for the IRQ lines. The IRQ lines are always biased and terminated.
Important: Connectors wired for other Mistic 200 controllers may not be compatible with the G4LC32. Use the
connectors provided and refer to the configuration label for wiring information.
CONFIGURATION
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