Campbell CS120A, Инструкция по эксплуатации

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Instruction Manual
37
17 Dew heater override 0-1 0 = Allow the sensor to automatically control the
dew heaters
1 = Turn the dew heaters off 0
18 Hood heater override
(1)
0-1 0 = Allow the sensor to automatically control the
hood heaters
1 = Turn the hood heaters off 0
19 Dirty window
compensation 0-1 0 = No compensation applied
1 = Compensation for dirt on lenses applied.
The sensor will compensate for up to 10% signal
loss due to dirt per lens. 0
20 Use CRC-16 0-1 0 = Disable command line CRC-16 checking
(2)
1 = Enable command line CRC-16 checking
Note: this does not affect communications via
DevConfig or terminal emulator.
0
21 Sensor power down
voltage 7-30 PSU Input voltage level below which the sensor
will enter low power mode. This is usually used to
protect batteries. 7.0
22 Relative humidity
(3)
threshold
1-99 Threshold at which the sensor will define
obscuration as liquid or dry if a CS215 is fitted. 80%
(1) Hood heater override needs to be set to `1’ (off) when either no hood heaters are installed or
the hood heaters have no power connected to them. This will save power as the relay is not
enabled at low temperatures in this mode.
(2) If disabled the sensor does not check the validity of received data against the checksum sent.
It is, however, recommended that checksum checking is enabled to remove any chance of the
sensor being configured incorrectly by accident.
(3) CS125 only.
14. Command line mode
The command line interface is broken down into three major commands. These
are GET, SET and POLL. The GET command is used to request all current user
settable values from the sensor. The SET commands sets user settable values and
the POLL command is used to request the current visibility and/or alarm
conditions from the sensor.
The sensor can be configured to expect any commands sent to it to include a valid
checksum. For simple commands, e.g. GET and POLL, fixed value checksums
can be used (see the example programs). For more complex SET commands the
checksum needs to be calculated (see Appendix B). The use of the checksum is
disabled by default. It is recommended that the checksum functionality is enabled
where possible, especially when long cable runs are used, or in electronically
noisy environments.
14.1 The SET Command
The set command is used to configure the sensor via the command line. The SET
command is a single space delimited string that can be sent from any data logger
or PC equipped with serial communications. The SET command and the ‘Device
Configuration Utility’ software access identical settings within the sensor, please
refer to the ‘Device Configuration Utility’ section of this document for a more
detailed breakdown of the setting available here. This command is used to change
the default power up state of the sensor. See Section 14.2 if a setting is going to be
changed on a regular basis e.g. heater controls.
See Section 12 for more information on the values used by the `SET’ command.