Preparation For Wiring 2.5 - Partlow MRC 7800 Installation, Wiring, Operation Manual

P 8
AGE
FIGURE 2-1
12 5/8
7 1/2
(320.7
mm) (190.5
mm)

Preparation for Wiring 2.5

2.5.1 WIRING GUIDELINES
Electrical noise is a phenomenon of the typical industrial environment. The following are
guidelines that must be followed to minimize the effect of noise upon any instrumentation.
2.5.1.1 INSTALLATION
Listed below are some of the common sources of electrical noise in the industrial environ-
ment:
* Ignition Transformers
* Arc Welders
* Mechanical contact relays
* Solenoids
* Motors
Before using any instrument with devices listed previously, the instructions below should be
followed:
1. If the unit is to be mounted in the same panel as any of the listed devices, separate them
by the largest distance possible. For maximum electrical noise reduction, the noise
generating devices should be mounted in a separate enclosure.
2. If possible, eliminate mechanical contact relays and replace them with solid state relays. If
a mechanical relay being powered by the unit's output device cannot be replaced, you may
wish to use a solid state relay to isolate the instrument from this source of noise.
3. A separate isolation transformer which feeds only instrumentation should be considered. If
available, it can isolate many noise sources from the AC power input of the unit.
4. If the unit is being installed in an existing installation, a review of the wiring in the existing
area should be done.
EC3
EC1
EC4
EC2
(64 mm)
(384.2
15 1/8
mm).
WIDTH OF COVER
2 19/32
(65.9mm)
9/32
DIA.(7.1mm)
13 1/2
(342.5 mm )
13 15/16
(354 mm)
13 3/16
(335 mm)
3 3/4
(92.3 mm)
4 11/16
(119.1 mm)
Mounting
(2)
Bracket
7/32
(5.5 mm)