Operation; Standby Mode; Table 4-1. Status Of Internal Pneumatics During Standby Mode - Teledyne T750 User Manual

OPERATION

The portable calibrator can be in either Generate mode or Standby mode (set in the
Generate menu). When in basic Generate mode, the calibrator is engaged in producing
calibration gas mixtures. When in Standby mode, the calibrator and its subsystems are
inactive, during which time other operations can be completed, such as configurations in
the Setup menu. The calibrator can also automatically perform several functions in a series
of steps called a Sequence (Section 4.2.1), first programmed by the user through the
Setup>Sequence menu (Section 3.3.7) or a Level if using Dasibi (Section 4.2.7.6),
programmed through the Setup>Levels menu (Section 3.3.8).
S M
4.1.
TANDBY ODE
When the portable calibrator is in Standby mode, it is at rest. All internal valves are closed
except the diluent inlet valve. The mass flow controllers are turned off. On units with O
generator and photometer options installed, these subsystems are inactive.
The Setup>Gas submenu is only available when the instrument is in Standby
•
mode.
Some functions under the Setup menu, those that conflict with accurate creation of
•
calibration gas mixtures, automatically place the calibrator into STANDBY mode
when activated.
• The MFCs are turned OFF when the calibrator is Standby mode, so their pressures
are not monitored during that time. This prevents erroneous MASS FLOW
WARNING messages from appearing.
Note
Table 4-1 shows the status of the T750's various pneumatic components when the
calibrator is in STANDBY mode. Figure 4-1 shows the pneumatic flow path during
Standby mode, including options.

Table 4-1. Status of Internal Pneumatics During Standby Mode

CYL IN
X
1 Only present if multiple
2 Present with photometer option.
3 Present with O3 Generator option.
In instruments with optional O
mode so that the generator can continue to operate at its most efficient temperature.
083730750B DCN8606
The calibrator should always be placed in Standby mode
•
(Generate>Standby)
calibration gas.
The last step of any calibration sequences (Section 3.3.7)
•
should always be the STANDY instruction.
VALVES
(X = Closed; O = Open)
D = Deenergized; E = Energized
DILUENT IN GPT O3 GEN 2, 3
O D D
cal gas MFC option is installed.
generators installed, airflow is maintained during Standby
3
when not needed
MFCs
PHOT M/R 1 CAL1 CAL2
Reference Phase OFF OFF
3
to produce
PHOT
1 DILUENT PUMP 2
OFF OFF
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