Siemens 7MF4033 series, Руководство пользователя

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UMSITRPDS3-1 Installation
November 2010
4-29
4.5.3 Electrical Conduit and Cable Installation
All electrical conduit and all signal wires must be supplied by the user. Access to electrical terminals is
described in Section 4.5.2.3.
For conduit and cable routing, refer to user’s installation drawings. Installation of conduit and cabling
should follow the guidelines given below.
4.5.3.1 Conduit
•
Transmitter conduit inlets accept male conduit fittings. Refer to the transmitter’s rating plate and
Section 9.1 to determine whether conduit threads are 1/2-14 NPT or M20 x 1.5.
Seal NPT fittings with Teflon tape; seal M20 fittings with a soft-setting sealing compound rated for at
least 105°C (221°F).
•
When routing conduit, avoid areas that might subject the conduit to chemical or physical abuse or
areas with high electromagnetic interference/radio frequency interference (EMI/RFI) conditions.
•
Install conduit for field wiring.
•
If a high humidity environment can exist and the transmitter is located at a low point in the conduit
run, install drain seals at the transmitter’s conduit inlets to prevent condensation from entering the
transmitter. See Figure 4-16.
•
Remove all sharp edges or burrs from conduit that may damage wires; 18-inches of flex conduit is
recommended at each transmitter.
MG
0035
4a
Conduit Drain
Explosion Proof
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+
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+ +
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1
2
3
3
4
4
1
2
Drain seal in conduit coupling
Install conduit seal: Crouse-Hinds Type EYS or equivalent
3
4
Plug unused electrical entrance
Electrical conduit
FIGURE 4-16 Conduit Drain and Explosion Proof Installations