Honeywell HPM, Сервисная инструкция

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7 IOP Calibration Procedures
7.10 RHMUX IOP Calibration Procedure
456 HPM High-Performance Process Manager Service R688
Honeywell December 2020
Calibration procedure
Use the following procedure to calibrate an RHMUX IOP.
Step
Action
1
Using the HPM Status display at the console, place the RHMUX IOP in the Idle state.
2
Verify on the LLMux (RHMUX) display that the RHMUX IOP is configured for the
correct frequency.
3
Disconnect any field wires from channels 1 and 16.
4
On the LLMux (RHMUX) IOP display, place the RHMUX IOP in the Calibrate mode.
5
At the RHMUX FTA, verify that the voltage at the factory calibration pin is a logic one
which indicates that field calibration is in process.
Verify that the FTA’s Status LED is off and not blinking randomly.
6
Connect the calibration device to the channel 1 input terminals. Set the voltage to 100
mV, +/- 5 uV.
7
Short the channel 16 input terminals for a minimum of 0.1 of a second and then remove
the short. The firmware uses burnout to read the state of the channel 16 input. The
multiplexer digitizes the input in about 4 seconds, turns on the Status LED for 0.2
seconds, and turns the Status LED off if the voltage is within 20% of the expected
voltage. If not, the Status LED will blink twice.
8
Set the calibration voltage to 20 mV, +/- 5 uV. Short the channel 16 terminals again for
a minimum of 0.1 of a second and then remove the short. The RHMUX IOP will do
another conversion. The firmware extracts a new slope coefficient for the reference
diode and overwrites the field the previous field calibration factor.
9
If the calibration is successful and complete, the Status LED returns to the normal
blinking cycle. The RHMUX IOP will respond to a “Status” command with an “OK”
status. If the calibration was not successful, t
he response will be “CALIBRATION
FAILURE.”
Calibration failure
If during the calibration procedure, the RHMUX IOP senses that the calibration voltage is off by more
than 20%, the Status LED will blink twice
(0.2 of a second on, 0.2 of a second off) to indicate a failure. This requires that the calibration voltage be
checked and reset to the proper value. Again, the channel 16 input terminals must be shorted for a
minimum of 0.1 of a second and then opened to cause the RHMUX IOP to retry the voltage. If the
calibration sequence can not be successfully completed, power must be cycled off and then on again to
exit the calibration sequence.