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Table of Contents
King Probe
- Description: CSIRO-KING Liquid Water Content Probe
- Manafacturer: Particle Measureing Systems Inc.
- Model: KLWC-5
- Serial Number: SN-PMI-1058-0704-86 (Purchased fall 2008)
- Accuracy: +/- 15% LWC (See http://www.atd.ucar.edu/raf/Bulletins/B24/kingLwc.html)
- 200 um Drops: - 50% LWC (See Walter Strapp paper, “Measurements of the response of hot-wire LWC and TWC probes to large droplet clouds”)
Instrument Requirements
- Power: 28 VDC 10 Amps [Heaters] 28 VDC 70-120 Watts [Source: Paul LeHardy]
- Weigth: 1.8 Kg (4 lbs) [Total weight for control Unit, display and sensor] [Source: Paul LeHardy]
- Size: width - 6 inch. Height - 12 inch. Depth - 12 inch. [Control Unit] [Source: Davie Delene]
- Hot Wire Size: 1.92mm Measured October 20, 2010 [Source: Aaron Ness]
- Hot Wire Diameter Size: 1.92mm, Length - 47.30mm Measured August 25, 2011, new element changed out on June 1, 2011 [Source: Aaron Ness]
Calibrations
- Calibration plots from calibration done on December 30, 2010 from 4550 to 4880 seconds from midnight.
Problem
During April 8, 2011 flight the signal voltage was negative.
Cause
The wire on the A/D board was connected backwards for this flight.
Solution
The A/D wires were switched. The King probe was tested on the ground to valid that there is positive voltage when the probe is turn on. Labels were put King Probe A/D wires.
Problem
During L3COM flight on November 24, 2004 the King Probe wire broke.
Cause
Normal to sometimes break.
Solution
King Probe wire replace after the flight.
Problem
During the TAMDAR Turbulence flight on September 9, 2005 the King Probe wire broke.
Cause
Flight encounted some heavy rain and a little hail. This resulted in breaking the broken wire.
Solution
King Probe wire replace after the September 13 ferry flight to Fairbanks, Alaska. The King probe power was not turn on during the ferry flights.
Problem
King Probe voltage possibly high. Probe does not match water content measured by other probes.
Solution
Varied voltage on a fan blowing on the hot wire of the probe. Dave and Aaron measured the following on 10/25/11 on data file 2011_10_25_19_24_46: 28.0 vdc on fan read 0.940 on King display, and current mesured 2.56 amps. 23.0 vdc, 0.88 displayed, 2.48 amps. 20.0 vdc, 0.84 displayed, 2.42 amps. 15 vdc, 0.75, 2.29 amps. 10.0 vdc, 0.64, 2.11 amps. 5.0 vdc, 0.27 displayed, 1.43 amps. 0.0 vdc, 0.29, 1.47 amps. re-did 28.0 vdc, 0.96 displayed, 2.57 amps.
Problem
11/5/2011 Flight. Anti-ice not working.
Solution
11/8/2011. 5 amp fuse blown in the back of the display head in 3rd rack. Heater/Element issue. Resoldered spare heaters on a new element. Need to check out w/ freeze spray to confirm all fixed. Called Bill Dawson at DMT to order spare heaters. DMT still sells the elements and the heaters. I will get a quote on cost and log the part numbers.