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DSGH Installation and Operation Guide
Calibration
To correlate the 4 mA ... 20 mA to the process value, set the span of the
current loop output.
A direct measurement of the current is preferable: hook the meter up in
series with the instrument and the DCS. However, if you know the
resistance of the DCS, use a voltage measurement to calculate the current.
Measuring the current loop output
Before a current loop calibration:
Connect an ammeter or the DCS to:
•
Terminal connections 13 (mA +) and 14 (mA -)
•
Test points H1 and H2
•
Anywhere along the current loop
Make sure there is a 250 – 800
load on the current loop. If no load or
an insufficient load exists on the loop, it may require temporary
Note:
The current loop and process spans are independent and set
separately. The current loop span sets the density indications for
the 4 mA and the 20 mA outputs. The process span sets the
endpoints of the calibration curve.
Current meter
Voltmeter
Terminal block pins
13 and 14
Detector
housing
DCS
R
t
Terminal block pins
13 and 14
Detector
housing
R
t
Summary of Contents for DSGH
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Page 4: ...2 DSGH Installation and Operation Guide NOTES ...
Page 8: ...6 DSGH Installation and Operation Guide NOTES ...
Page 12: ...10 DSGH Installation and Operation Guide Preface NOTES ...
Page 32: ...30 DSGH Installation and Operation Guide Installation Mounting the DSGH gauge ...
Page 56: ...54 DSGH Installation and Operation Guide Calibration NOTES ...
Page 94: ...92 DSGH Installation and Operation Guide Diagnostics and repair NOTES ...
Page 98: ...96 DSGH Installation and Operation Guide NOTES ...
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