Future Design MCTB 4.3, User Manual

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MCTB
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Step 2 of the procedure is calibrating the span of the A to D converter. To calibrate the input high coefficient,
adjust the resistance source to 300 ohms (for RTD input) or 20mA (for current input). If calibrating a voltage
input, adjust the voltage source to 60mV for 0-60mV input, 1VDC for 0-1VDC input, 5VDC for 0-5/1-5VDC input
or 10VDC for 0-10VDC input. Allow several seconds for the source signal to stabilize. Record the current
calibration coefficient valu
e and press the “Calibrate” button. A dialog will be shown indicating the new
coefficient is being calculated. DO NOT alter the source signal during the process. Once complete, the dialog
will close and the new coefficient value will be shown.
If the new coefficient value is -1999 or 1999, the calibration failed. Check the source connections and insure
the proper signal is applied. Press the Calibrate button to repeat the process or press the coefficient
display/entry field and enter the previous coefficient value recorded to return the loop/limit back to its previous
state. To skip the input high coefficient calibration or to complete the calibration procedure, press the “Next”
button.
Once the calibration steps have been completed, adjust the reference signal to the low and high end of the
operational range to verify that the process value matches the reference signal within the accuracy limits for
the input type.
Once the input has been verified to display the proper value according to the input reference signal, reconnect
the control sensor to the loop/limit control and press the “Done” button. This will return to the main Calibration
screen.