ircon Modline 4, Installation And Operation Manual

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All MODLINE 4 Series instruments use multilayer
coatings on their lenses to define their spectral prop-
erties and to increase optical transmission. Although
these coatings satisfy military specifications for durabili-
ty, all coated lenses are susceptible to damage from
harsh environments.
Whenever moisture, oils, or active chemicals con-
dense on a coated lens, the optics become stained.
The stains are difficult to clean and tend to break
down the coating. Use of an air purge will help prevent
condensation and damage in harsh environments, but
only the purge is supplied with clean air.
If necessary, install air filters in the air path.
NOTICE
2–6
Section 2 — INSTALLATION
2. 7b . Mechanical Mounting
The MODLINE 4 may be mounted either by the
front flange or by the mounting pad at the bottom
of the casting. Mounting accessories are available
as described in Section 5.
Procedures for aligning the unit on target are pro-
vided in Section 2.10.
If the proposed mounting surface is at earth
ground potential, you can mount the Sensor direct-
ly to this surface with the bolts supplied. If the sur-
face is not at earth ground potential, insulate the
Sensor casting from the surface by inserting an
insulating gasket and using insulating mounting
hardware. See Section 2.15 for grounding details.
NOTE: Maximum Signal Cable length is 3000 ft
(1000 m). Plan your mounting location and cable
route accordingly.
2.7c
.
Ambient Temperature
STANDARD CASTING
The MODLINE 4 with a standard casting has an
operating case temperature range of 32 to 150°F
(0 to 66°C).* If you allow the temperature to go
beyond these limits, incorrect temperature indica-
tions or damage to the instrument may result.
If you think the case temperature will approach the
upper temperature limit due to ambient conditions,
consider some type of auxiliary cooling. An IRCON
Model WA-3 Water Cooling Accessory is one solu-
tion. (See Section 5 for details on this and other
accessories.)
A heat shield between instrument and target as
shown in Fig. 2.7 is another possible solution to
excessive ambient temperatures. Air cooling by
means of a blower fan or IRCON AA-3 Air Purge is
another option. Call IRCON for other suggestions.
If the MODLINE 4 is to be located in the cold envi-
ronments where its temperature may go below the
lower temperature limit, consider some form of
heating. For example, install the instrument in a
temperature controlled enclosure or wrap it with
electrical heater tape.
*Operating case temperature range for Series 43-
04F and 43-02C are 50 to 113°F and 10 to 45°C,
respectively.
Operating case temperature range for all Series 22
is 30 to 130°F (0 to 54°C).
2.7e . Spot Size and Resolution
Observe the guidelines in Section 2.9 regarding
spot size and resolution. Above all, make sure the
target surface is at least twice the spot size (or the
spot size is less than half the target size) at the
viewing distance.
WATER-COOLED CASTING
A MODLINE 4 with a water-cooled casting can
operate in ambient temperatures up to 400°F
(200°C) with a minimum water flow rate of 20
gal./hr (75 liter/hr) of tap water at less than 75°F
(24°C).
CABLE TEMPERATURE LIMITS
Maximum temperature rating of the Signal Cable is
220° F (100°C) for standard PVC-covered cable or
400°F (200°C) for IRCON-supplied silicone rubber-
covered cable. Plan the cable routing accordingly.
2.7d . Air Purge
If dust, oil, vapors, etc. collect on the lens, low tem-
perature indications will result. For instruments with
standard castings, use an IRCON Model AA-3.
Air Purge to avoid the problem; a MODLINE 4 with
water-cooled casting has an integral air purge.
NOTE: For Series 43-04F or 43-02C do not use a
Model AA-3 Air Purge with a Model WA-3 Water
Cooling accessory. With these two accessories
combined, the front edge of the AA-3 will obstruct
the Cone of Vision and cause errors in the temper-
ature readings.
A supply of clean, dry instrument air or filtered dry
plant air at a flow rate of 6 ft
3 /min (0.17 m 3 /min) is
recommended.