Iring the, Eter, 1 power wiring – NOSHOK 2100 Series Field Upgradeable Dual Input Process Indicator User Manual

Page 7: Wiring overview, Emc installation guidelines

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7

WIRING OVERVIEW

Electrical connections are made via screw-clamp terminals located on the

back of the meter. All conductors should conform to the meter’s voltage and
current ratings. All cabling should conform to appropriate standards of good
installation, local codes and regulations. It is recommended that power supplied
to the meter (DC or AC) be protected by a fuse or circuit breaker.

When wiring the meter, compare the numbers embossed on the back of the

meter case against those shown in wiring drawings for proper wire position.
Strip the wire, leaving approximately 0.3" (7.5 mm) bare lead exposed (stranded
wires should be tinned with solder). Insert the lead under the correct screw-
clamp terminal and tighten until the wire is secure. (Pull wire to verify
tightness.) Each terminal can accept up to one #14 AWG (2.55 mm) wire, two
#18 AWG (1.02 mm), or four #20 AWG (0.61 mm).

EMC INSTALLATION GUIDELINES

Although this meter is designed with a high degree of immunity to Electro-

Magnetic Interference (EMI), proper installation and wiring methods must be
followed to ensure compatibility in each application. The type of the electrical
noise, its source or the method of coupling into the unit may be different for
various installations. Listed below are some EMC guidelines for successful
installation in an industrial environment.

1. The meter should be mounted in a metal enclosure, which is properly

connected to protective earth.

2. With use of the lower input ranges or signal sources with high source

impedance, the use of shielded cable may be necessary. This helps to guard
against stray AC pick-up. Attach the shield to the input common of the meter.

3. To minimize potential noise problems, power the meter from the same power

branch, or at least the same phase voltage as that of the signal source.

4. Never run Signal or Control cables in the same conduit or raceway with AC

power lines, conductors feeding motors, solenoids, SCR controls, and

heaters, etc. The cables should be run in metal conduit that is properly
grounded. This is especially useful in applications where cable runs are long
and portable two-way radios are used in close proximity or if the installation
is near a commercial radio transmitter.

5. Signal or Control cables within an enclosure should be routed as far away as

possible from contactors, control relays, transformers, and other noisy
components.

6. In extremely high EMI environments, the use of external EMI suppression

devices, such as ferrite suppression cores, is effective. Install them on Signal
and Control cables as close to the unit as possible. Loop the cable through the
core several times or use multiple cores on each cable for additional protection.
Install line filters on the power input cable to the unit to suppress power line
interference. Install them near the power entry point of the enclosure. The
following EMI suppression devices (or equivalent) are recommended:

Ferrite Suppression Cores for signal and control cables:

Fair-Rite # 0443167251 (RLC #FCOR0000)
TDK # ZCAT3035-1330A
Steward #28B2029-0A0

Line Filters for input power cables:

Schaffner # FN610-1/07 (RLC #LFIL0000)
Schaffner # FN670-1.8/07
Corcom #1VR3

Note: Reference manufacturer’s instructions when installing a line filter.

7. Long cable runs are more susceptible to EMI pickup than short cable runs.

Therefore, keep cable runs as short as possible.

8. Switching of inductive loads produces high EMI. Use of snubbers across

inductive loads suppresses EMI.

Snubber: RLC#SNUB0000.

3.0 W

IRING THE

M

ETER

3.1 POWER WIRING

AC Power

Terminal 1: VAC

Terminal 2: VAC

DC Power

Terminal 1: +VDC

Terminal 2: -VDC

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