PST MICHELL Instruments MDM300, User Manual, Page: 16 / 70

MDM300 User Manual
8 97122 Issue 16.2 June 2022
INTRODUCTION
1.3.2 Status Display Indications
‘ Initializing Internal Sensor’
This is displayed immediately after the instrument has been powered up, and indicates
that the sensor is being heated up to accelerate equilibrium with the moisture in the
sample gas. This has the effect of drying the sensor out, and results in the ‘undershoot’
seen in the first stage of the measurement process.
‘Measurement in Progress’
This is displayed after the sensor initialization has finished, and indicates that the sensor
is running through the following initial measurement procedure:
1. Undershooting the dew-point
2. Making a first estimate
3. Running a QRA (Quick Response Algorithm), if necessary
Once the message has disappeared, this indicates that the instrument has finished
its accelerated approach to the actual dew point. Depending on the conditions it may
continue to respond for a number of minutes more, before settling on (or tracking) the
actual measured dew point.
Other Status Display Indications
Internal sensor
error
Dew-point reading out of range (> +30 / < -120 °C)
Internal thermistor
error
Sensor internal temperature reading out of range (> +100 /
< -40 ° C) or
Thermistor fault
External sensor
error
External sensor input out of range (< 4 mA / > 20 mA)
Battery low Battery level low - recharge as soon as possible
Battery low -
recharge now
Battery level critical - recharge immediately
Log finished
Log file has reached the maximum of 10,000 logs and logging has
been stopped
Internal sensor not
found
Could not detect internal sensor on power up
Default CONFIG file
used
Config. file missing, new file created and default settings used