CPT6010 Operating Instructions
25
Digital Pressure Transducer
CPT6010
7.3 Pressure Standard
Mensor recommends the use of appropriately accurate primary pressure standards when calibrat-
ing this instrument. Such standards should be sufficient so that when the techniques of the ISO
Guide to the Expression of Uncertainty in Measurement (GUM) are applied, the instrument meets
its accuracy statements as required by ANSI/NCSL Z540, or other applicable standards. The
same requirement applies to the vacuum gauge used to set the zero offset on absolute calibrations.
The recommended absolute pressure level for setting the zero offset on an absolute transducer is
between 600mTorr absolute and 20% of the active transducer’s span.
7.4 Calibration Medium
The recommended calibration medium for sensors up to 6000 psi is dry nitrogen or clean, dry
instrument air. Hydraulic media (water or oil for example) are recommended for ranges above 6000
psi. Hydraulic media can be used with lower ranges, however, special techniques must be used in
filling the connection lines and transducer.
7.5 Calibration Process
Please notice that the commands listed in this section are shown in the same style as those in the
Operation section. These are the bare commands seen by the CPT6010, stripped of all program-
ming idioms. Depending on the specific language used to generate them, these commands may
have to be preceded by or enclosed in various symbols for transmission. For this procedure it is
assumed that a single CPT6010 is connected to the host computer, and that its assigned address
is unknown.
The model, serial number, and software version number of the CPT6010 being calibrated can be
obtained by sending: #*ID?<cr><lf>.
7.6 Correction Value Query
The stored correction for zero offset or the span correction factor can be retrieved over the bus. The
returned values have six significant digits plus a decimal point and a sign. To see the stored values
send either:
#*ZC?<cr><lf> or #*SC?<cr><lf>
These commands may be useful in determining the actual changes in zero and span over time.
Unauthorized alterations of the values can be detected by comparison with previously recorded
correction values.
i
Notice
Each command issued to either calibration parameter must be followed by
the SAVE command to make it permanent. Otherwise, the changes will be
lost the next time the CPT6010 loses power.
