Maintenance for 2001N, 2002N, and 1800R Manual

MOD30ML and Modcell Maintenance Manual
COMMUNICATIONS
10. Access the Instrument Status Display and click on the command line at the bottom of the
screen. Type R VERSION and click on Enter. This command returns the version of any
instrument connected to the ICN, even MOD 30. If the instrument responds, confirm that
the reported version agrees with the type of instrument that is being tested. The version
return data is listed in Section 3.4.3.
11. If you are unable to establish communications in Step 10 proceed as follows:
• If you are unsure of the link configuration, first access the serial port setup menu
again and change the baud rate to another setting. In most cases, the link is set at
9600 or 19200.
• If the problem still exists, change the parity setting. If a Mini Link is being used,
always set the parity at none. The data and stop bits are likely to be set at 8 and 1
respectively.
• If unable to establish communications, disconnect power and remove all analog
and communications modules, except for the ICN module being used. Restore
power and try to communicate again via the R VERSION command.
• If the problem still exists, do the following:
1. Disconnect power.
2. Disconnect all instruments from the ICN, other than the one being tested.
3. Ensure that the address switch on the ICN module is set at a different
address than the switch on the ICN interface board in the link.
4. Restore power and try to communicate again via the R VERSION command.
• If still unable to communicate, replace the ICN module, preferably with a Model B
version and terminator.
• If all previous procedures fail, replace the instrument.
4.2.2 Modbus Module Communication
Troubleshoot problems with Modbus module communication as follows:
NOTE: The extended Modbus communications required for diagnostics and downloading is
supported by the 2033N and 2034N modules only. On Modcell, the Identity module
firmware must be at least version 4 Logic, version 3 Regulatory, Batch, Advanced.
Refer to Section 9 for details of hardware and software compatibility.
1. Remove power from the instrument.
2. Note the switch settings on the Modbus module. Two rotary switches are used to select
the address. The address is indicated in hexadecimal, by the flat side of the spindle, with
A through F representing 10 through 15.
3. Set the COMM DEFAULTS switch to YES. This forces the module to communicate at
9600 baud, 8 data bits, 1 stop bit and no parity, regardless of the database configuration.
4. If using an RS-485 module, set the TERM switch to NO. This switch provides pull-up and
pull-down resistors to stabilize the network. This function is defined by the Modbus
specification as the responsibility of the Modbus Master node, which is the PC in this
case. If the PC does not contain an RS-485 interface card with the required bus
stabilizing resistors, the TERM switch on one communications module on the network
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