Connecting
5.3 Step 2: Connecting signal cables
SITRANS F M TRANSMAG 2
26
Operating Instructions, 11/2009, A5E00102775-07
5.3
Step 2: Connecting signal cables
CAUTION
Lay the signal cables separately from cables with voltages > 60 V.
Avoid laying signal cables close to large electrical installations or use - if possible - only
shielded cables.
Note
In a wet environment, the signal cable for digital output 2 (terminals 3 and 4) must be
isolated when the feed-in voltage is more than AC 16V / DC 35 V.
Only use signal cables with twisted wire pairs.
1.
Push the signal cable through the cable gland up to the terminal strip. Lay the cable in a
loop before the cable glands so that moisture does not get inside the terminal box.
2.
Connect the lines according to the figure above.
3.
Fit end ferrules to fine-wire lines.
4.
Tighten the cable gland and check strain relief.
5.
Screw the lid to the housing and tighten it. You must not use any tools. The sealing ring
must be clean and undamaged.
6.
Mount the lid catch.
7.
For transmitters in remote design, also connect the housing to the local potential
equalization to which the appropriate sensor must also be connected.
HART requirements
● The full HART 5.1 specification only applies when using shielded cables.
● Use signal cables with twisted wire pairs if the analog output and pulse/frequency output
are used simultaneously and signals are transmitted in one cable.
● A load of at least 250 Ω must exist in the signal circuit (see also Technical data
(Page 73)) for error free communication via the HART protocol.
See also
Wiring devices with Profibus PA (Page 92)