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Sensor Suite

Info about subtletlies of the sensors.

Misc ToDo notes

  • [ ] get all changed SR300 modbus variables in proper format
  • [ ] change heater/fan write registers in control logic
  • [ ] check on met station operation (new heating mode, etc)
  • [ ] PWM speed control for LW VU01 fans? Not really.... could lower power?
  • [ ]
  • [ ]

Snow height

An acoustic pinger, Campbell 'Snowvue'/SR50measures snow height below the radiometer boom.

Radiation

The radiation suite is based on testing that Chris Cox for the "de-ice" experiment, comparing a range of radiometers in the Arctic

Shortwave — Hukseflux/"Hukx" SR30

A lightly heated and ventilated (internal to sensor package) shortwave. It only talks modbus (over RS-485 serial) and outputs diagnostic information about the fan speed/current, heater amperage, internal humidity, and tilt. The rs485->modbus comms can be finicky. You need a ~120 Ohm resistor at the termination (across c7-c8 terminals). Warning, modbus registers have changed from the SR30 to the SR300.

The default modbus address is supposedly 1. Ymmv. You must change the modbus address of one of the sensors to 2.

Misc troubleshooting tips:

If you want to see the serial data streaming realtime, open the Campbell terminal emulator and type: H; W; <RS485-C_Port>

RS485 data ground is sensitive, lots of problems over the years with ground loops. Also, make if you're getting nothing in the ascii output of the term make sure your D+/D- aren't flipped.

Longwave — Hukseflux/"Hukx" IR20

A radiometer with internal heat that we use in tandem with the external Hukx VU01 ventilator. This is an analog measurement (voltage readout )that includes a correction using an independent measurement of the temperature of the dome by thermistor.

We do not use the internal heater? Email Chris?

Warning: the new VU01 ventillators have a different wiring and fan speed output. See the new manual. To measure the fan freq you need a 10uF cap to ground and a 10 kOhm pull-up resistor to 5v at the pulse measurement port on the logger.

Direct/Diffuse — Delta T SPN1

This radiometer has a geometric mask and matrix of thermopiles that allow it to passively measure/estimate direct and diffuse shortwave.

Wires

Brown | Vcc +12 White | Gnd 0v Grn\Yel |Tx Black | Rx Blue | N/A

PTU Meteorology Boom — Vaisala Indigo 520

Fancy new met sensors, that sends communicates by Modbus TCP/IP. To connect, find the DHCP assigned IP and go to https://192.168.1.150:8443/. The Indigo treats the 3 sensors components as individual units. This means it can be logged with the logger and the computer at the same time which is... nice I guess. There is now a script called "log_indigo.py" that does this.