Campbell Scientific 27106T Gill Propeller Anemometer - Manual (Page 14)

27106T Gill Propeller Anemometer
Replace the tach-generator as follows:
1. REMOVE OLD GENERATOR ASSEMBLY
a) Remove propeller from anemometer.
b) Unthread generator housing collar. Pull generator housing away from
sensor connector and generator assembly.
c) Note position of generator wires on sensor connector pins. Unsolder
wires from pins and remove old generator assembly.
2. INSTALL NEW GENERATOR ASSEMBLY
a) Solder wires from new generator assembly onto proper sensor
connector pins. Verify correct polarity: CCW rotation produces
negative output voltage.
b) Slide generator housing over generator assembly. Firmly tighten
housing collar onto connector threads.
c) Check bearing torque to confirm it is within specification.
7. Troubleshooting
Symptom: No wind speed
1. Check that the sensor is wired to the single-ended channel specified by
the VoltSE instruction.
2. Disconnect the sensor from the datalogger and use an ohm meter to check
the Tach-Generator. The resistance between the white and black wires
should be about 32 ohms. Infinite resistance indicates an open coil; low
resistance indicates a shorted coil.
3. Verify that the Voltage Range Code, and Multiplier and Offset parameters
for the VoltSE instruction are correct for the datalogger type.
Symptom: Wind speed does not change
1. For the dataloggers that are programmed with Edlog, the input location
for wind speed is not updated if the datalogger is getting “Program Table
Overruns”. Increase the execution interval (scan rate) to prevent
overruns.
8. References
References containing additional information about the Gill Propeller
Anemometer are listed below in chronological order.
Holmes, R.M., Gill, G.C., and Carson, H.W., “A Propeller Type Vertical
Anemometer”, Journal of Applied Meteorology, Vol 3, 1964, pp. 802-804
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