Thermo Scientific 146i, Instruction Manual

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Optional Equipment
Permeation Oven
Thermo Fisher Scientific Model 146 i Instruction Manual 9-3
6. Replace the glass chamber assembly into the oven until the top of the
assembly is flush or slightly below the top of the oven.
7. Tighten the knurled screw finger tight. Do not use tools to tighten.
8. Tighten the white plastic retaining collar.
9. Replace the oven cover being careful to place the tubing and wiring into
the cover slot.
Computation of
Concentrations
The computation of the gas output level is shown in the following
information. Note that is assumed that all devices are properly calibrated
and that all flows are corrected to 25
°
C and 1 atm.
Permeation Tube:
Where:
R = permeation rate in ng/min
Q
0
= flow rate of gas (scc/min) into the charcoal scrubber during span mode
K = constant for the specific permeant = 24.45 / MW
MW = molecular weight
Oven Installation and
Configuration
Use the following procedure to install and configure the permeation oven.
1. Physically install the permeation oven and valves into the instrument
and connect the cables and plumbing.
2. From the Perm Oven Settings menu in the Service menu, select Perm
Oven Selection , then select 45
°
C .
Equipment Damage Do not use tools to tighten the knurled screw in the
following step.
Q
(K) (R)
= (ppm) Output
o