Tisch Environmental PUF+, Руководство оператора

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Tisch Environmental PUF+ Operator’s Manual
33
CALIBRATION
The CALIBRATE menu allow the user to calibrate the sensors used by the unit. The
CALIBRATE menu (shown below) list the sensors in the system, the associated raw sensor
values and the values using the current calibration. Pressing the ENT key will begin the
calibration process for the selected sensor. The LOAD FACTORY CAL and LOAD
DEFAULT CAL menu items will load the calibration values set at the factory or the default
values from the firmware. These can be useful when tracking down calibration problems.
The factory calibration values are preferred because they compensate for the normal
manufacturing variations which the default firmware calibration values do not.
CALIBRATE
Qsys:( 0) 0
► Tamb:(39000) 21.2
Tcjc:(21789) 26.9
Pamb:( 3713) 759
Pdif:( 552) -0.0
Pcal:( 332) 0.01
LOAD FACTORY CAL>
LOAD DEFAULT CAL>
Important Notes on Calibration
•
Sensors may be calibrated using from 1 to 5 calibration points. There are two
exceptions to this. The first is the Tcjc (cold junction compensation temperature). It
requires only a single point calibration. The second is the Qsys (system flow rate)
which requires 5 points per EPA guidelines.
•
Single point calibrations while possible, are not recommended (except for Tcjc).
Single point calibrations only adjust the offset (A0) of the sensor and do not
compensate for any changes in the gain (A1). If single point calibrations are used, the
user should verify the gain by checking additional points against a reference.
•
The ambient temperature (Tamb) is dependent on the cold junction compensation
temperature (Tcjc). The cold junction compensation temperature is used to correct
the voltage error introduced at the “cold junction” of the thermocouple circuit. This
sensor does not normally require calibration once it leaves the factory, but if you wish
to calibrate the Tcjc sensor you must locate the reference temperature probe near the
thermocouple connection on the electronics.
•
Flow calibration (Qsys) is dependent on other sensors in the system. It is therefore
critical that they be properly calibrated or verified before calibrating the flow.
•
If the unit has been powered off longer than 15 minutes, please allow 30 to 60
minutes for the electronics to warm up prior to calibrating a sensor. This is to