Micromod MOD: 1732N, 1733N External Mini-Link Users Guide - Manual (Page 15)

IB-23C004
TROUBLESHOOTING THE MINI LINK
SECTION 3
TROUBLESHOOTING THE MINI LINK
3.1 NO RESPONSE FROM LINK
A "No Response From Link" error indicates one or more of the following:
• The serial cable between the host computer and the Mini Link/EXT is incorrectly
installed. Verify connection between the host and the Mini Link/EXT as shown in the
tables in Appendix B.
• The Clear-To-Send function on the Mini Link/EXT has been enabled without enabling
the same function on the host computer. Install W16 to enable CTS on port A (DB9)
and install W17 to enable CTS on port B (DB25). Check the serial cable for proper
wiring.
• The controlling software (i.e., PC-30, etc.) has been directed to an incorrect or
unavailable serial port.
• The Mini Link/EXT has not been powered on.
• There is a communications parameter incompatibility between the External Mini Link
and the host computer. Verify that the switch and jumper settings are correct.
3.2 PARITY, FRAMING OR OVERRUN ERROR
Check the configured baud rate for the associated serial port of the Mini Link/EXT.
Confirm that the configured baud rate is the same as that expected by the controlling
software (see jumper settings for W2 - W15 in Appendix A).
3.3 NO RESPONSE FROM THE FIELD INSTRUMENTS
If communication has been established between the Mini Link/EXT and the host computer,
but the instruments on the ICN do not respond, compare your configuration to the
checklist below:
1. The ICN (+) lead of the two-wire interface is connected to the terminal block (+)
screw on the rear of the Mini Link/EXT.
2. The ICN (–) lead of the two-wire interface is connected to the terminal block (–) screw
on the rear of the Mini Link/EXT.
3. If using the isolation feature (see jumper setting for W1), there is a third wire
connected between the Mini Link/EXT terminal block GND screw and ICN ground on
the instrument termination panel.
4. The length of the ICN (including the total length of the physical two-wire bus between
each node on the ICN and the length of the instrument cables between the nodes and
the instruments) does not exceed 2000 feet or 609.6m.
3-1