infrared industries FGA, Руководство оператора

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T A C H O M E T E R
This menu screen allows the operator to select between a 2-cycle and 4-cycle engine. This option is required because
most 4-cycle ignition engines fire only on the compression stroke or every other crankshaft revolution. 2-cycle engines
fire with each revolution of the crankshaft so if your analyzer was set on 4-stroke (cycle) while measuring a 2-cycle
engine; your analyzer would display ½ your actual engine RPM. The same problem would occur if you had your
analyzer set to 2-stroke while measuring a 4-cycle engine only in this case the analyzer would display 2X or twice the
actual engine RPM. Engine equipped with DIS (Distributor-less Ignition System) along with some 4-cycle ignitions due
fire on the exhaust stroke. In these cases an accurate RPM reading can be achieved by simply setting the analyzer to “2-
stroke”.
Z E R O I N G
A U T O M A T I C A U T O - Z E R O
After power-up and the WARM-UP LOCKOUT phase has been completed, the unit will begin operating. The system
will use a graduated AUTO ZERO timing cycle in order to automatically initiate AUTO-ZERO cycles. As we have
seen above various operating modes may initiate an auto zero cycle. The system does not include these as being a part
of the AUTO-ZERO automatic cycle. The system does an AUTO-ZERO every time the system enters STANDBY,
(i.e. leaves a mode). After this AUTO-ZERO cycle the automatic cycle timing continues until the system leaves
STANDBY. The time period is normally fixed at about 10 minutes, but the ambient temperature affects the technical
requirement for an AUTO-ZERO cycle. Therefore the system varies the time in between AUTO-ZERO cycles based
on the ambient temperature and the changes in ambient temperature.
M A N U A L A U T O - Z E R O
The operator may initiate an auto-zero cycle any time the system is in STANDBY. If the operator pushes the ZERO
push button when the system is in CAL mode (the CAL indicator is ON), the AUTO-ZERO indicator will flash to
indicate that this may well be a bad time to zero the system (because in MEASURE mode the cell is likely to have gas
other than air in it).
A U T O - Z E R O S E Q U E N C E
In the AUTO ZERO mode:

The sample pump is turned on

The SAMPLE/ZERO solenoid is switched to the ZERO GAS and the sample cell is purged completely

The system acquires and stores new zero data
During this process the ZERO indicator light is on continuously. The AUTO ZERO cycles last about 25 seconds.