Siemens SITRANS SL, Руководство по эксплуатации, Страница: 29 / 212

SITRANS SL
Operating Instructions, 12/2010, A5E01132948-04
31
Application planning
3
3.1 Cable selection recommendations
Cable selection recommendations
Note

For a normal (non Ex) setup of SITRANS SL the cables are not part of the standard
delivery and should be ordered as an accessory.
 An Ethernet cable may be permanently connected via the receiver junction box. Ethernet
is needed for service and maintenance work. A permanently connected cable is
recommended when the SITRANS SL is located at an inconvenient physical location.
 With the receiver junction box mounted, the Ethernet jack inside the receiver unit may not
be used, unless the wires connected to the Ethernet screw terminals inside the receiver
housing have first been disconnected.
You can select your cable according to your requirements from the following table for
standard non-Ex analyzers SITRANS SL.
●
Suitable connection cables shall be selected depending on the electric interface used.
● The connection cable must provide both power and ground to the analyzer.
● Ethernet cables shall be of type CAT-5, or better, with a shield (FTP or STP).
Cabling guidelines
Sensor connection cable Connection cable
Shield Yes, required Yes, required
Configuration Twisted Pairs Twisted Pairs recommended
Number of conductors
 4 x 2 or
 2 x 2 + 3
(2 pairs for comm. & synch + 3 for
power and ground)
 Full connection;
Modbus: 10x2 (twisted
pair)

PROFIBUS: 1 x 2 + 4
(PROFIBUS DP hybrid cable)

Modbus: 1 x 2 + 3 or
3 x 2 (twisted pair)
Conductor cross
section
Minimum 0.34 mm
2
Minimum 0.34 mm
2
(Consider voltage drop for too long
cables)
Cable diameter 8 ... 12 mm with provided cable gland  8 ... 12 mm with provided small
cable gland
 13 ... 18 mm with provided large
cable gland