ircon Modline 4, Installation And Operation Manual

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Section 1 – INTRODUCTION
1.1 GENERAL DESCRIPTION
MODLINE 4 is an infrared thermometer with a built-in two
wire transmitter. Power it up with a 16 to
4 0 volt direct
current source and you get a 4 to 20 mA current (maximum)
that varies linearly with temperature. You can use this
current to operate a 4 to 20 mA indicator, recorder, con-
troller or datalogger – or a combination of devices in
the series. Figure 1.1 shows the basic electrical circuit.
This instrument is built for long, trouble-free service in even
the harshest environments. Everything is packaged in
sealed aluminum casting rated NEMA 4. The instrument
can be ordered with a water-cooled casting for operation
in high ambient temperatures.
The lens is recessed and sealed in the front of the casting.
A screw-on back cover with torquing slots gives access to
the adjustments and connections (see figure 1.2). A 1/2
inch NPT conduit hub is provided for wiring. NOTE: The
back cover of the water-cooled enclosure has a pair of
torquing studs.
The MODLINE 4 is easy to install, operate and maintain.
The lens is pre-adjusted and sealed so you don’t have to
make optical adjustments. Just choose a clear sight path
with no obstructions, aim the sensor at the object you want
to measure and read the temperature on your indicator.
The controls on the back panel allow you to adjust for
emissivity of the material you are measuring and for the
most suitable response time for your process. If the instru-
ment includes a peak picker (block D of model number
= 1), an additional control is provided for peak picker
decay time. As long as your process stays the same, you
will make these adjustments only once when you set
up the instrument.
The high-level current signal (20 mA maximum) minimizes
noise problems often associated with long cable runs.
Twisted pair cable with an overall shield is all you need
for most applications.
Seven different MODLINE 4 series that differ in spectral
responses, cover a wide variety of processes. Temperature
ranges covering 0 to 2500°F and 0 to 1300°C are available.
Note: General illustrations in this manual that show the
standard MODLINE 4 casting also apply to instruments
with water-cooled castings.
1-1
Fig. 1.1 - BASIC MODLINE 4 ELECTRIC CIRCUIT
Fig. 1.2 - MODLINE 4 REAR VIEW (WITH
COVER REMOVED) and FRONT VIEW
Note: standard enclosure shown .