Operation; Default Configuration; Hart ® Operation During Fault - Honeywell Searchpoint Optima Plus Operating Instructions Manual

MAN0905_Issue 7_07/17
During normal operation, the 4-20 mA output represents 0-100 %FSD. The output is linear.
Analogue output below 4 mA represents diagnostic information. If the Searchpoint Optima Plus measures
a negative gas reading, the analogue output will remain at 4 mA until the negative gas warning threshold
is reached (-3 %FSD to -6 %FSD depending on the gas being measured) at which point it will signal a
Warning.

5.1 Default Configuration

The tolerance on the nominal current output value is ± 0.2 mA.
During Warning status, the Searchpoint Optima Plus will continue to monitor gas, and will revert to Gas
Reading status if a gas reading is detected.
If a Warning is indicated, schedule maintenance to investigate and rectify the cause. If left unattended, the
unit is likely to enter Fault status, when it will be offline.
The Warning, Inhibit and Overrange signal levels can be configured using the HART
a Honeywell Analytics Field Service Engineer as follows: -
* For ATEX compliance, the warning value should not be set > 3 and < 5 mA. If the warning value is set
higher than 4 mA, the output signal will toggle between the warning value for 1 s and the current gas
5.2 HART Operation during Fault
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HART communication requires > 1 mA current output for transmission, therefore if the HART
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the Searchpoint Optima Plus goes into Fault the HART
It is possible to configure the Fault output level of a Searchpoint Optima Plus unit with HART
This can be done during commissioning (see Commissioning using HART
HART Operation during Fault).
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5. Operation

Status Current output
Fault
Warning
Gas Reading 4 – 20 mA
Overrange
Inhibit
Parameter
Warning* 0 mA to 6 mA
Inhibit 1 mA to 3 mA
Overrange 20 mA to 21.6 mA
reading for 9 s.
communications will not work.
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30
Searchpoint Optima Plus with optional HART
< 1 mA
3 mA
21 mA
2 mA
Range
Communications, Configure
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output
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Operating Instructions
2108M0550
communications, or by
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version of
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to be 1 mA.
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