Maintenance 6
IR7000
56
Teledyne Analytical Instruments., - Rev. 3
5. Identify the parts and location of the Optical Bench Assembly.
See Figure 6-2.
•
Sample Cell – This is a glass tube internally coated with
gold or silver. It is installed in a front-to-back orientation in
the analyzer. Instruments designed to measure trace levels
use a longer sample cell which is oriented diagonally
within the case. Instruments designed to measure high
percentage levels employ a much smaller cell that directly
connects the IR source and detector.
Figure 6-2: Optical Bench Components
•
Source Holder –The source holder is the black mounting
block on one end of the sample cell.
•
IR Source – The IR source is the silver metal cylinder
inserted into the source holder.
•
Detector – The detector is the square block at the other end
of the sample cell. It normally carries a label reading
“Detector #XXXX” Where XXXX refers to the particular
detector for that instrument only. The detector cannot be
interchanged with other instrument.
•
Optical Bench Mounting Plate – The long metal plate
running under the sample cell, detector and source holder is
the optical mounting plate. It is used to secure the optical
bench components in proper alignment.
•
Couplers on Sample Cell – There are 5 plastic parts and 4
O-rings that are used to couple the cell to the detector and
source. From the detector end of the cell to the source they
are:
•
Sample Cell End, Detector Side
• Pressure
Plate