ONICON F-5100 MOD Network - Manual (Page 6)

11451 Belcher Road South, Largo, FL 33773 • USA • Tel +1 (727) 447-6140 • Fax (727) 442-5699 • [email protected]
F-5100-MOD Flow Meter Network Interface Installation Guide 05/14 - 0669-6
Page 6
1.4 NETWORK SIGNAL CONNECTIONS
MODBUS RS485, 2-wire (half-duplex) serial output connections are made at terminals C2 and C3
as shown below. Incoming and outgoing RS485 cable shield wires should be connected together,
but must not be connected to the meter.
F-5100 Terminals
6
5
4
3
2
1
6
5
4
3
2
1
C B A
C B A
2
3
+
-
Shields
Outgoing cable
Incoming cable
IMPORTANT NOTE
For the first 6-10 seconds after power is applied to the meter it will respond to the default settings
(19200 Baud, even parity). If the meter does not receive a valid poll with these settings within
this time interval, the meter will be configured for Baud rate and parity according to the value
recorded in register 349.
i
1.5 RS485 BAUD RATE, BIASING AND TERMINATION
1.5.1 Baud Rate and Parity
Every ONICON F-5100 is individually programmed at the factory with application specific data
provided by the customer during the process of ordering the meter. This normally includes the
Baud rate and parity settings. If the Baud rate and parity settings were provided, the meter will be
configured to the appropriate settings.
If this information was not provided, the meter default settings are:
Baud rate: 19200 Parity: Even
The available Baud rate settings are 9600 and 19200. The available parity settings are odd, even
or none. Both the Baud rate and the parity setting can be changed via the MODBUS network.
Register 349 is a holding register used to set the Baud rate and parity. Write to this register using
function code 16, write multiple registers. The table below provides the register values that must
be written to achieve the corresponding Baud rate and parity settings. Once the new value has
been written to the register, power must be cycled to the meter for the change to take effect.
Register Value Baud Rate Parity
0 19200 Even
2 19200 Odd
4 19200 None
5 9600 None