Inputs and Outputs Wiring

Conform to code

Instrument wiring should conform to regulations of the National Electrical Code.

Recommended maximum wire size

Table 7-1 Recommended Maximum Wire Size

Gage Number

mm2

Description

14

2.081

power, relays, and PE

 

 

(protective earth)

 

 

 

18

0.823

inputs

 

 

 

18

0.823

isolated outputs

 

 

 

Shielded wiring for locations with interference

In applications where plastic conduit or open wire trays are used, shielded milticonductor 22 gage (0.326 mm2) or heavier signal input wiring is required.

Avoiding interference

Instrument wiring is considered Level 1, per section 6.3 of IEEE STD. 518 for plant facilities layout and instrumentation application. Level 1 wiring must not be run close to higher level signals such as power lines or drive signals for phase fired SCR systems, etc. Unprotected input wiring in high electrical noise environments is subject to electromagnetic, electrostatic, and radio frequency interference pickup of sufficient magnitude to overload input filters. The best instrument performance is obtained by keeping the interfering signals out of the instruments altogether by using proper wiring practices.

References

Refer to the following when wiring the unit.

IEEE STD. 518, Guide for the Installation of Electrical Equipment to Minimize Electrical Noise Inputs from External Sources.

Appropriate wiring diagram supplied with electrode mounting or preamplifier module.

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UDA2182 Universal Dual Analyzer Product Manual

January 2009

Page 128
Image 128
Honeywell UDA2182 manual Recommended maximum wire size Recommended Maximum Wire Size, Avoiding interference, References