Teledyne 6200E - Sulfides Analyzer - Manual (Page 213)

Model 6200E Instruction Manual Theory Of Operation
M6200E Rev: A1 213
10.3.1. sample gas Flow
The Flow of gas through the M6200E UV Fluorescence H
2
S Analyzer is created by a small internal
pump that pulls air though the instrument.
PMT
EXHAUST TO OUTER
LAYER OF
KICKER
REAC
T
IO
N
CELL
P
URG
E
FLOW
SENSOR
FLOW / PRESSURE
SENSOR PCA
SAMPLE
FILTER
INSTRUMENT CHASSIS
EXHAUST GAS
OUTLET
VA
CUU
M
M
AN
IF
O
L
D
SAMPLE GAS
INLET
KICKER EXHAUST TO PUMP
PUMP
FLOW
CONTROL
ASSY
SAMPLE
PRESSURE
SENSOR
UV
LAMP
HYDROCARBON
SCRUBBER
(KICKER)
SPAN GAS INLET
ZERO AIR INLET
SAMPLE
CHAMBER
2
1 3
SO 2
Scrubber
MOLYBDENUM
CONVERTER
SO
2
Å H
2
S
H 2 S / SO 2
MODE VALVE
Gas Flow when multigas version of
6200E analyzer is measuring SO 2 .
Figure 10-7: M6200E Gas Flow and Location of Critical Flow Orifice
10.3.2. Multigas Measurement & H
2
S Æ SO
2
Switching Valve.
When installed and operating the multigas measurement option allows the instrument to be
configured so that it can measure either or both H
2
S or SO
2
. A Teflon ® switching valve, activated
under CPU control via the I 2 C buss and the relay board directs the sample gas stream through the
so2scrubber and H
2
S Æ SO
2
converter (H
2
S measurement mode) or directly to the sample
chamber bypassing the H
2
S Æ SO
2
converter, allowing the analyzer to measure SO
2
.
When the multigas option, (Option 82) is activated, this valve switches back and forth allowing
the analyzer to measure both SO
2
and H
2
S (see Section 5.5). The cycle for this operation is