Endress+Hauser iTEMP TMT71, Руководство по эксплуатации

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Operating menu and parameter description iTEMP TMT71
78 Hauser
Navigation Application → Current output → Failure current
Prerequisite The High alarm option is enabled in the "Failure mode" parameter.
Description Use this function to set the value the current output adopts in an alarm condition.
User entry 21.5 to 23 mA
Factory setting 22.5 mA
Adjustment of the analog output (4 and 20 mA current trimming)
Current trimming is used to compensate the analog output (D/A conversion). Here, the
output current of the transmitter can be adapted so that it suits the value expected at the
higher-level system.
Procedure
1. Start
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2. Install an accurate ammeter (more accurate than the transmitter) in the current loop.
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3. Switch on current output simulation and set the simulation value to 4 mA.
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4. Measure the loop current with the ammeter and make a note of the value.
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5. Set the simulation value to 20 mA.
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6. Measure the loop current with the ammeter and make a note of the value.
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7. Enter the current values determined as adjustment values in the Current trimming 4 mA / 20 mA
parameters
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8. Deactivate simulation
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9. End
Current trimming 4 mA
Navigation Application → Current output → Current trimming 4 mA
Description Use this function to set the correction value for the current output at the start of the
measuring range at 4 mA.
User entry 3.85 to 4.15 mA
Factory setting 4 mA
Additional information The trimming only affects the current loop values from 3.8 to 20.5 mA. The failure mode
with Low Alarm and High Alarm current values is not subject to trimming.