Rosemount 2081 pH, Инструкция по эксплуатации

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2.4.3 2-Point Calibration (cont.)
Remove the sensor from buffer #1. Rinse Sensor in water
(Deionized), then place in the 2nd buffer solution. The sen-
sor is placed in the second buffer solution and that buffer
value is entered into the 2081. The 2081 will calculate the
new slope from the two buffer values.
2.4.4 Compare the 2081 pH reading to the buffer value
that the sensor is in. If the display doesn’t read the buffer
value, then enter the buffer value into the 2081, by per-
forming
Sections 2.4.2 - 2.4.3 ; substituting the buffer #2
value for the buffer # I value.
If display reading is correct, go to
Section 2.4.3, step 5. .
2.4.5 After the buffer value #2 value is entered into the
2081, it calculates the sensor’s slope. The transmitter and
sensor are now calibrated. Upon installation into the
process, a Standardization should be performed to
improve the reading accuracy (refer to
Section 5.4 after
completing the Quick Start-up procedure).
Leave the sensor in buffer #2.
2.5 Current Output Check
Check the current output of the transmitter; sensor should
still be in buffer #2 (i.e., 10 pH).
2.5.1 Calculate the proper current output for the buffer
being used, with the adjacent formula.
Example: Sensor is acclimated in 10 pH buffer.
Transmitter is factory configured for 0-14 pH full-scale
range, and 4-20 mA output.
Current output should read 15.43 mA.
2.5.2 Remove the sensor from buffer #2. Rinse Sensor in
water(Deionized), then place in the 1st buffer solution.
Check the current output with the sensor acclimated to
buffer #1.
2.5.3 Calculate the proper current output for the buffer
being used, with the mA output formula.
Example: Sensor is acclimated in 4 pH buffer.
Transmitter is factory configured for 0-14 pH full-scale
range, and 4-20 mA output. Current output should read
8.57 mA.
NOTE
If the pH buffer readings are accurate and the
current output values are within tolerance, then
the unit is calibrated and ready to be placed
into service.
2081 Display
10
10
.
.
05
05
=
Buffer #2
10.00 pH
?
+
Buffer Value #2
+
Buffer Value #1
mV reading
pH V
a
lue
2081 calculates the
sensor slope
(ideal is 59.1 mV/pH)
mA Buffer Value
=
(
––––––––––––––––
)
X 16 + 4
output Full-scale Range
mA 10.00 pH
=
(
––––––––––––––––
)
X 16 + 4
output 14
= 15.43 mA ± .16
mA Buffer Value
=
(
––––––––––––––––
)
X 16 + 4
output Full-scale Range
mA 4.00 pH
=
(
––––––––––––––––
)
X 16 + 4
output 14
= 8.57 mA ± .16
MODEL 2081 pH SECTION 2.0
QUICK START-UP PROCEDURE
pH Sensor
Buffer #2
(i.e., 10 pH)
Water (DI)
Rinse Sensor
➛