Teledyne T360, Operation Manual, Page: 51 / 358

Teledyne API Model T360/T360M Operation Manual Getting Started
49
This valve option is intended for applications where zero air is supplied by a zero
air generator like a bottle of N
2
and span gas are being supplied by Gas Dilution
Calibrator like the Teledyne Instruments Model 700 or 702. Internal zero/span
and sample/cal valves control the flow of gas through the instrument, but because
the calibrator limits the flow of span gas no shutoff valve is required.
In order to ensure that span gas does not migrate backwards through the vent line
and alter the concentration of the span gas, a gas line not less than 2 meters in
length should be attached to the vent span outlet on the rear panel of the analyzer.
To prevent the buildup of back pressure, this vent line should not be greater than
10 meters in length.
SAMPLE
PRESSURE
SENSOR
O3 FLOW
SENSOR
Sample Gas
Flow Control
P
ur
ge G
as
Fl
ow
C
ontrol
Purge Gas
Pressure Control
Sample / Cal
Valve
Zero / Span
Valve
Ex
te
rna
l C
O
2
S
crubb
er
(Opt
io
n 5
3 0
nly
)
COM
NO
NC
NO
COM
NC
Figure 3-16: Internal Pneumatic Flow – Ambient Zero/Ambient Span
The following table describes the state of each valve during the analyzer’s
various operational modes.
Table 3-9: Ambient Zero/Ambient Span Valve Operating States
Mode Valve Condition
Sample/Cal Open to SAMPLE inlet
SAMPLE
(Normal State)
Zero/Span Open to IZS inlet
Sample/Cal Open to ZERO/SPAN valve
ZERO CAL
Zero/Span Open to IZS inlet
Sample/Cal Open to ZERO/SPAN valve
SPAN CAL
Zero/Span Open to PRESSURE SPAN inlet
The minimum span gas flow rate required for this option is 800 cm
3
/min.
07272B DCN6552