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6.2 Calibration example
Using the internal references
In this example the internal references within the
BA558C are used to calibrate the rate display.
Except for steps 1, 2 and 8 the procedure is
identical to that in the previous example in section
6.1 The advantages of using the internal
references are that the instrument does not have
to be disconnected from the measurement loop
and no calibration equipment is required.
Steps
Enter the programming mode
1 & 2
The BA558C may be recalibrated
without disconnection from the 4/20mA
measurement loop. With any input
current between 4 and 20mA put the
instrument in the programming mode by
simultaneously pressing P and E.
Assuming a security code has not
already been entered the instrument will
respond by displaying 'root' which is the
first function in the main menu.
Steps
Perform as described in the
3 to 7
previous calibration example
see section 6.1
Step 8
Calibrate the rate display
Scroll through the main menu until 'SEt'
is displayed. Press P and the instrument
will display 'ZErO', pressing P will reveal
the existing rate display at 4mA. Using
the Up, Down and P push-buttons enter
the required zero display of 0.0 Press E
to enter this calibration figure. The
instrument will display ‘Ent’ for a few
seconds before returning to the 'ZErO'
prompt.
Press the Up push-button and the
instrument will display 'SPAn'. Pressing
P again will reveal the existing display at
20mA. Using the Up, Down and P push-
buttons enter the required display of
1100 Press E to enter this calibration
figure. The instrument will display ‘Ent’
for a few seconds before returning to the
'SPAn' prompt.
Steps
Perform as described in the
9 to 14
previous calibration example see section
6.1
