Appendix a, A.1 analog output calibration, A.1.1 analogue output zero – ENMET EX-6175 User Manual
Page 25: A.1.2 analogue output span
EX-6175
ENMET Corporation
22
Appendix A
A.1 Analog Output Calibration
The analogue output is that of a current source. In order to calibrate the output it is necessary to monitor the output signal. This
can be performed in one of two ways:
Current measurement:
Connect an ammeter (or multimeter set to measure current in the mA range) in series with the analogue output.
Advantage:
Direct measurement of output.
Disadvantage: The analogue output has to be disconnected to allow the connection of the meter.
Voltage measurement:
Permanently connect a 10R resistor in series with the analogue output. When calibration is required, connect a voltmeter
(or multimeter set to measure voltage in the mV range) across the 10R resistor.
Advantage:
No need to disturb wiring between
EX-6175
and control unit.
Disadvantage: Measurement accuracy dependent upon resistor tolerance.
A.1.1 Analogue Output Zero
•
Monitor the current sourced from the analogue output of the EX-6175 using a suitable method.
•
From the menu system select menu option: E: 4 and press ENTER.
•
Using the INCREASE and DECREASE buttons; adjust the output to the required level (4mA or 40mV).
•
Press ENTER.
N
OTE
: Pressing the MENU button rather than the ENTER button exits the zero feature without performing the calibration.
•
Press the MENU button to close the menu system.
N
OTE
: The ZERO factor will be displayed momentarily on exit.
A.1.2 Analogue Output Span
Always zero the analogue output prior to performing a span operation.
•
From the menu system select menu option: E: 5 and press ENTER.
•
Using the INCREASE and DECREASE buttons; adjust the output to the required level.
•
Press ENTER button.
N
OTE
: Pressing the MENU button rather than the ENTER button exits the span feature without performing the calibration.
•
Press the MENU button to close the menu system.
N
OTE
: The ANALOGUE OUTPUT SPAN factor will be displayed momentarily on exit.
–
+
FGD10
Analogue Output
(4 – 20mA)
Control
Unit
mA
+
Meter range:
0.004A – 0.020A
4mA – 20mA
–
+
FGD10
Analogue Output
(4 – 20mA)
Control
Unit
10R
mV
+
Meter range:
0.04V – 0.20V
40mV – 200mV