Michell Instruments MDM300 I.S, User Manual

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MDM300 I.S. User’s Manual
52 97213 Issue 5, October 2017
APPENDIX B
Table 13 shows the status flags associated with each bit of the status register. If a
status flag is set high then the associated condition exists. If it is set low, then that
condition does not exist.
Status Register
bit in Hex
Message Details
0x0002 = BIT 2
Internal sensor
error
Dew-point reading out of range (> +30 / <
-120°C)
0x0004 = BIT 3
Internal thermistor
error
Sensor internal temperature reading out of
range (> +100 / < -40°C) or
Thermistor fault
0x0008 = BIT 4
External sensor
error
External Sensor Input out of range (< 4 mA /
> 20 mA)
0x0010 = BIT 5
Battery low
Battery level low - recharge as soon as possible
0x0020 = BIT 6
Measurement in
progress
Internal dew point not stable
0x0040 = BIT 7
Internal dew point changing <0.2°Cdp over a 3
minute interval
0x0080 = BIT 8
Log fi nished
Log fi le has reached the maximum of 10,000
logs and logging has been stopped
0x0100 = BIT 9
Internal sensor not
found
Could not detect internal sensor on power up
0x0200 = BIT 10
Default CONFIG fi le
used
Con fi g. fi le missing, new fi le created and default
settings used
0x0800 = BIT 12
Initializing Internal
Sensor
Indicates system in purging phase
Table 13 Status Register Flags
For the example given in Figure 35, from Table 13, Hex 28 translates, reading from right
to left, as bit 4 set ‘
External sensor error’
and bit 6 set ‘
Measurement in progress’
.
Therefore, at the time that these log points were taken, the external sensor was out of
range and the internal dew point was not stable.