Service Submenu - GE Hydran 201i Instruction Manual

Hydran* 201i Instruction Manual

5.5.4 Service Submenu

The Service submenu allows the user to:
• Read the value of the Hydran 201 sensor parameters.
• Test the H201 sensor operation.
• Read the battery voltage.
• Set the parameters of the battery alarm.
• Read the service data of the H201 sensor.
5.5.4.1 Sensor Cal Data
This function gives access to the Hydran 201 sensor parameters. Each sensor has its
own set of parameter values; the values are indicated on the Test Certificate and Data
Sheet supplied with the Hydran 201Ti.
• SerialNumber: Serial number of the H201 sensor (engraved under the sensor
connector).
• B, M, N, S, A1, A2, A3, A4, A5 and A6: The ten parameters of the H201 sensor in a
normalized format (integer numbers).
- The H201Ti calculates the gas level in ppm by performing two readings: The
H201 sensor temperature (provided by the thermistor incorporated in the
sensor body) and the sensor output (gas level). The calculation also requires
these ten parameters (from B to A6).
- These ten parameters characterize the behavior of the H201 sensor by
modeling the offset, linearity and sensitivity fluctuations of the sensor
according to the temperature.
• CheckSum: Checksum of the above values. This value is added to the list to avoid
erroneous values from being entered.
This submenu does not allow you to modify the displayed values. To change the
values, use the NewSensor submenu (Section 5.5.8).
The values of the H201 sensor's ten parameters are stored in the H201Ti's nonvolatile
memory.
5.5.4.2 Force Sensor Test
This function is used to test the operation of the Hydran 201 sensor. The Hydran
201Ti verifies the sensor by injecting a small dc current in the sensor for a few seconds
and then reading the gas level. This test correlates strongly with the sensor response to
dissolved gases and thus allows the H201Ti to reliably assert the actual condition of the
sensor. The result is immediately interpreted by the microprocessor as follows:
• If the sensor is operating properly, the message Good is displayed, but no
message is recorded in the historic data file Events. The H201Ti's display returns
to the Main Display mode (see Section 5.2.2) after the H201 sensor output signal
has returned to normal (two minutes).
MA-033 Rev. 14.0, 12-Nov-18
Page 71