Gill Instruments Limited
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MetStream 100
Page 12
Issue 2
Doc. No. 1955-PS-001
March 2016
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.
Maximum cable lengths for supported communication networks
Cabling (unused wires)
Any unused wires in the connecting cables should be connected to ground preferably at
the user equipment end.
Cabling protection
Cables should be secured:-
With cable clamps or equivalent at regular intervals such that the hub box cable
gland does not support the cable weight.
Away from any mounting bolts to prevent chaffing of the cable.
NOTE:
Install appropriate strain relief support to the cable if required.
Earthing
To ensure correct operation and for maximum protection from lightning, a separate
lightning rod system is recommended to protect the system.
You can also earth the MetStream through its mountings or by connecting a grounding
cable to the MetStream Earth Terminal Post. Clean off any paint etc. that might prevent a
good connection to the Earth structure.
When you connect the screened communications cable ensure that the screen has a
connection to the MetStream Case.
5.1.2
Ethernet to Ethernet Connection
An Ethernet compatible cable should be used.
Generic description:
–
2 Twisted pairs for Data only application.
4 twisted pairs for Data and Power over Ethernet (POE) applications.
CAT5 or higher RJ45.
8 pin 8 contact type (8P8C).
Max Cable Length 100 metres (Cat 5, Cat 5e, Cat 6).
Types - straight or crossover depending on system connection.
Shielded Twisted Pair (STP) recommended or Unshielded Twisted Pair (UTP).
Communication
format
Baud rate
Max. cable length
RS232
19200
6.5M
RS422
19200
1000M
