Table 2 Recommended Belden Cable Types; Table 3 Maximum Cable Lengths For Supported Communication Networks - Gill Instruments MetPak II User Manual

Installation
Page 14
Communication Cabling
MetPak II/MetPak II R has five communication connection options:

USB (using the 1.8m Gill USB cable, Part No. 1723-10-051).

RS232

RS422

RS485 (two wire point to point)
 SDI-12
It is important that the cable is appropriate for the chosen communication network.
The following sections describe the recommended types and maximum lengths of
cable in each case.
NOTE. A 15-metre, 6-pair cable (wires stripped at each end) suitable for
RS232/RS422/485 or SDI-12 communication is available from Gill Instruments
(Part No. 1723-10-053).
Cable Type
Wire type:
Wire size:
Cable outer diameter:
For RS422/485 operation the cable should contain twisted pairs screened to match
the application.
The following table shows an example manufacturers' reference; other
manufacturers' equivalents can be used.

Table 2 Recommended Belden cable types

Application
SDI-12 or RS485
Digital RS232
Digital RS422
Cable length
The maximum cable length is dependent on the chosen communication method.
The following table shows the maximum cable lengths for the supported
communication protocols at the given baud rates, using the recommended cable. If
any problems of data corruption etc are experienced, then a slower baud rate
should be used. Alternatively, a higher specification cable can be tried.

Table 3 Maximum cable lengths for supported communication networks

Communication format
RS232
RS422/RS485
SDI-12
MetPak II and MetPak II R User Manual
©
Gill Instruments Ltd
24AWG
7x32 AWG.
6-8mm (to match the hub box gland).
No. of Pairs
2
3
4
Baud rate
19200
19200
1200
Belden Ref.
9729
9503
9504
Max. cable length
6.5M
1000M
90m (300ft)
Last Change
09 March, 2012