NOSHOK 756 Series Digital Pressure Transmitters - Manual (Page 18)

15
5.4 Calibration without Pressure
Determine the current reference values for the zero point and the span to be entered
in the transmitter before calibration. This is done as follows:
5.4.1 Zero Point Calibration
T :I:GB>C:I=:=N9GDHI6I>8EG:HHJG:D;I=:A>FJ>9HHJG;68:I=6IB::IHI=:O:GDED>CI
T 9?JHII=>HEG:HHJG:>CEGDEDGI>DCIDI=:H:CHDGHCDB>nal pressure range.
T (JAI>EANI=>HEGDEDGI>DC7NB6C9699BIDI=:G:HJAI
This produces the calculated current (value I
calc
), which is entered in the transmitter
and used to programm the zero point (0%).
Example:
EG:HHJG:IG6CH9J8:GL>I=B76GCDB>C6AEG:HHJG:C::9HID7:pro-
FJ>9HHJG;68:L>I=69:CH>IND;>HB67DK:I=:9>6E=G6zero point producing a pressure of 100 mbar.
.=>HB:6CHI=6II=:9:K>8:H8JGG:CIK6AJ:BJHI7:H:IIDBL=:CE:G;DGB>C<69GN
:BEIN86A>7G6I>DC
5.4.2 Span Calibration
T :I:GB>C:I=:=N9GDHI6I>8EG:HHJG:D;I=:A>FJ>9HHJG;68:L=>8=8DGG:HEDC9HIDI=:
span end-point.
T 6A8JA6I:I=:9>;;:G:C8:D;I=:EG:HHJG:K6AJ:7:IL::Cspan end-point and zero
ED>CI6C99>K>9:I=>H9>;;:G:C8:7NI=:CDB>C6AEG:HHJG:G6C<:D;I=:H:CHDG
T (JAI>EANI=>HEGDEDGI>DC7NB6C9699BIDI=:G:HJAI
This produces the calculated current (value I
calc
), which is entered in the transmitter
and used to program the span end-point (100%).
The measurement range between zero point and span end-point will be stored as
span.
I
c alc
Zero point pressure (0%) 100 mbar
-:CHDGHCDB>C6AEG:HHJG:B76G
------------------------------------------------------------------------------------------------ B B + B = =
6A>7G6I>DC06AJ:
calc
6A>7G6I>DCD;O:GDED>CIL>I=DJI9>HEA6NL>I=DJIEG:HHJG:
6A>7G6I>DC06AJ:
... to I
meas
= I
calc
... to I
meas
= I
calc