The atomiser is available in two versions: Micromiser 12 with rotational speed variable over the range of 1,500 – 12,000 RPM to produce spray droplets of 60 – 300 µm VMD. This atomiser should be used for application on crops and ground targets.
It is recommended that the flow control valve should be fitted in a by-pass line to return excess flow from the pump to the tank. MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
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Fig. 3 – Mounting of Atomiser and Connections PRESSURE MEASURED AT INLET WITH WATER FLOW (ml/MIN) Graph 1 – Inlet Pressure vs Flow Rate MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
If necessary, the open ends of the tubes should be under a cover to prevent ingress of water from rain or washing. Fig. 4 – Orientation of Atomiser Vent Tube MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
(22 AWG). 3.4.1. Power Supply Both the Micromiser 12 and Micromiser 16 atomisers require a 24 V DC power supply. This will normally be provided by the main battery of an electrically powered UAV. If the available supply is greater than 24 V it will be necessary to install a step- down (buck) voltage converter.
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8000 9000 10000 11000 12000 ATOMISER RPM Graph 2 – Current Consumption of Micromiser 12 vs Atomiser RPM and Flow Rate FLOW (ml/MIN) Graph 3 – Current Consumption of Micromiser 16 vs Flow Rate at 24 V Input MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
3.4.2. Atomiser Speed Control (Micromiser 12 Only) The speed of the Micromiser 12 atomiser is determined by the voltage on pin 4 of the motor connector. This pin is pulled up to the internal +5 V supply of the motor controller by a 1 K Ohm resistor and an external resistor between pin 4 and ground forms a potential divider to set the control voltage.
Fig. 5 – Schematic of Speed Control for Micromiser 12 3.4.3. Atomiser Speed Output A pulse output is provided to enable the rotational speed of the atomiser to be measured without the use of an external tachometer or stroboscope on the disc.
Irrespective of legislation, Micronair advise the users of their equipment that all possible care must be taken to ensure the health and safety of the user and personnel in the vicinity of the spraying operation.
Flow (l/min) = spraying speed (km/hr) x track spacing (m) x application rate (l/ha) Example: A UAV fitted with four Micromiser 12 atomisers is to apply 10 l/ha using a spraying speed of 12 km/hr and a track spacing of 5 m, so: Total flow from UAV = 12 km/hr x 5 m x 10 l/ha = 1.0 l/min...
Graph 5 shows the measured VMD (Volume Median Diameter) of spray droplets from the Micromiser 12 at rotational speeds of 1,500 – 16,000 RPM when spraying plain water. Graph 5 shows the relationship between measured VMD (Volume Median Diameter) of spray droplets and liquid flow rate from the Micromiser 16 when operated from a 24 V supply.
Graph 6 – Spray Droplet Size vs Flow Rate for Micromiser 16 with 24 V Supply When using a Micromiser 12 atomiser the atomiser speed must be set either by an external control resistor or a potentiometer as described in Section 3.4.2 or by the UAV flight control system as described in Section 3.4.4.
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Replace the atomiser disc as described above The outside surfaces of the atomiser can be cleaned with a cloth moistened with water or a suitable solvent for the liquid that had been sprayed. MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
Defective atomiser motor Replace motor assembly or return atomiser to Micron Sprayers Ltd for repair Atomiser vibrates whilst Contaminated or damaged Clean disc or replace if operating atomiser disc damaged MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
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Fig. 6 – Components of Micromiser Atomiser MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
Cap screw, M2 x 16 CBP3325 Feed nozzle 2 mm bore CBP3324 Atomiser disc EX7199 Protective cap 8.2. Cable Assembly with Moulded M12 Connector Cable, 22 AWG x 2 m: CBP3430 MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
= 0.067 bar 1 atmosphere = 14.70 pounds/sq in = 1.01 bar 1 bar = 14.50 pounds/sq in = 0.98 atmosphere 1 kilopascal = 0.01 bar = 0.145 pounds/sq in MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
APPENDIX I Interface with Flight Control System MICRONAIR MICROMISER 12 & 16 ATOMISERS FOR USE ON UAVs...
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P/P ripple. Op amp U2 is a high impedance buffer for the speed (tacho) output pulse output of the Micromiser 12 (pin 2). This is required only if the output is to drive a low impedance or capacitive load.
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Notes Micronair is the registered trademark of Micron Sprayers Limited, Bromyard, United Kingdom. Every care has been taken in the design of this equipment and the preparation of this Handbook. However, Micron Sprayers Limited cannot accept responsibility for errors or the consequences thereof.
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