ircon Modline 4, Инструкция по установке и эксплуатации

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However, make sure the cable resistance at the
length you plan to use between the MODLINE 4
and the power supply will not cause an excessive
voltage drop. As an example, a 3000-foot length of
18-gauge cable may develop a voltage drop of
0.65 V when carrying 20 mA full-scale current. The
power supply voltage must be sufficient to accom-
modate this voltage drop and still supply normal
operating voltage for the MODLINE 4.
Keep the MODLINE 4 system wiring away from
high power or r-f wiring and avoid hot areas that
can damage the cable. If needed, high-tempera-
ture cables are available that can withstand 400°F
(200°C).
INSTRUMENT AND WIRING ENCLOSURE
Cabling enters the MODLINE 4 through a conduit
hub threaded for 0.5-inch conduit. The cord grip
has a bushing (grommet) that accepts cable diam-
eters from 0.225 to 0.350 in. (5.72 to 8.89 mm).
IMPORTANT: The cord grip assembly must be
tightened sufficiently following wiring installation to
provide the NEMA 4 rating of the MODLINE 4.
If you ordered your MODLINE 4 with the peak
picker option and are installing an external switch,
select a five-conductor twisted cable with overall
shield to feed through the cord grip.
NOTE: If plant practices or electrical codes require
the use of conduit, use the appropriate conduit fit-
ting in place of the cord grip.
SPECIAL INSTRUCTIONS FOR EEC
COMPLIANCE
In order for the MODLINE 4 to be immune to RF
susceptibility, either all wiring to the sensing head
must be run in conduit or a single overall shielded
cable must be used. The shield must be 360°, ter-
minated at the sensing head using the special
cable shield grip adapter provided. To maintain
electromagnetic immunity, only Indicators and
Power Supplies that meet EMC Directive
and carry the CE Mark can be used
with the MODLINE 4.
SELECTING AND PLANNING CABLING
After you have mounted all system components,
proceed with the electrical wiring. We recommend
a three-conductor twisted cable with overall shield.
The most practical wire sizes to use for the signal
loop are 14- to 18-gauge.
If the instrument you have ordered has a peak
picker and you plan to wire an external peak picker
control switch, select a five-conductor twisted
cable with overall shield to feed through the cord
grip. A 18-gauge wire size is required to support
an external peak picker.
The longest run of wiring will usually be from the
MODLINE 4 to the Power Supply and Indicator.
Cable lengths up to 3000 ft (1000 m) are accept-
able for most installations. (This limit on cable
length also applies to the peak picker wiring.)
2–17
Section 2 — INSTALLATION
2.1
3
CABLE SELECTION
and
MODLINE 4 WIRE TERMINATIONS
Risk of Personal Injury
I
n order for the MODLINE 4 to meet EMC
Directive, the Indicators and Power
Supplies must also meet the Directive and carry
the CE Mark.
!
!
CAUTION
CAUTION