Scott Instruments 087-0007G Safety, Setup, Operation & Maintenance Manual Download

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Model 4688-IR / 4679-IR
Operation & Maintenance Manual

Manual #087-0007G, 10/2003

STEP 3 - Without touching the sapphire window at the top of the mirror
assembly (oil can absorb infrared radiation), dip the mirror assembly in a
small quantity of

fresh

reagent grade isopropanol (e.g., Fisher Scientific

#A416-20). Agitate thoroughly and repeat as necessary.
STEP 4 - Using a source of

dry

compressed air, clean away any

accumulations. Ensure that the assembly is dried thoroughly.
STEP 5 - When the mirror assembly is clean, replace its dust filter and gently
screw it back into the case fitting taking care not to overtighten (mirror
assembly should be finger-tight). Retighten the set screw. Grasp the base of
the heater wire and gently plug it into the heater wire connection pin. Replace
the dust shield, taking care to align the twist-lock pins with the corresponding
slots on the dust shield cage. Gently turn the dust shield cage to the right until
the twist-lock fitting locks in place.
When the transmitter has been repowered and warmed up for 1/2 hour, use
the Up or Down arrow key to scroll to the F.AGC parameter in the FACT menu
and touch the magnet to the Enter key. See the next page for gaining access
to F.AGC. The transmitter will analyze the reflectivity of the mirror support
assembly and adjust the gain applied to the detectors. This function will take
about 2 minutes to run. If successful, the LCD will read “SEt”. If "ERR"
appears, perform steps under "Performing F.AGC Function" Step 3 on page
59. If "ERR" appears again you will need to replace the mirror assembly.
Apply a source of clean air to the sensor (p/n 077-0019) and zero the unit after
5 minutes. Use the "Z" key to return to the main screen.

Replacing the Emitter

Although the emitter has been selected for
performance and reliability, it may eventually fail
and need to be replaced (estimated life is
greater than 2 years). The need for emitter
replacement will be indicated by a fault output
from the transmitter (factory default = 3.2 mA)
and the fault code dF.XX (where X is any
number between 0 and 4) on the LCD display.
On transmitters with optional relays, the fault
relay will also be triggered.
STEP 1 - Before replacing the emitter, cycle the
transmitter power off and on. If this clears the
fault indication, there is no need to replace the
emitter.
STEP 2 -

Remove power from the

transmitter

and remove the dust shield by gently turning it to the left until the

twist-lock fitting unlocks, and then pulling downward.
STEP 3 - Grasp the base of the heater wire and gently pull downward to
unplug it from the heater wire connection pin. Loosen the set screw and
remove the mirror assembly dust filter and gently unscrew the mirror
assembly taking care not to touch the sapphire window.
STEP 4 - Two components will be visible inside the case fitting. One, the

POWER

SWITCH

Place in the OFF position

before removing Display /

CPU board stack. Ensure

power switch is in

the OFF position prior to

replacing board stack.

Case Fitting

Make sure the

lamp assembly

is flush, or