Constant pressure, variable rate
Rate follows the valve duty cycle, so droplet size and pattern stay put.
BT Smart Flow
BT Smart Flow — PWM Nozzle Control System
Pulse-width modulation drives every nozzle separately. Pressure stays constant, droplet size does not drift, and the applied rate holds even through a turn.
The difference
It modulates time, not pressure
A conventional sprayer changes the rate by changing pressure, which changes droplet size and spoils the spray pattern.
With PWM the nozzle valve opens and closes dozens of times per second and the rate follows the duty cycle, while pressure is held constant. Droplet size and spray angle stay the same across the whole speed range.
Features
What PWM changes in the field
Turn compensation
Each nozzle is metered for its own ground speed, so coverage stays even through a turn.
Per-nozzle shut-off
Individual nozzles close, giving clean field boundaries and sharp wedge corners.
Variable rate application
Prescription maps drive different rates across the field.
Alternating nozzle operation
Neighbouring nozzles fire in turn at high frequency, keeping the pattern intact at very low rates.
Real-time monitoring
Every nozzle's status is on screen; a blocked tip is noticed immediately.
Turn compensation
What happens in a turn
On a 24 m boom the outer tip travels far further than the inner one during a turn. With a single rate for the whole boom, the inside is overdosed and the outside underdosed.
Videos are FJDynamics ATS Ultra promotional material, used here for explanation.
Technical
The PWM hardware we use
Our installations use FJD ATS Ultra PWM tip control hardware. Figures from the manufacturer.
| Controller | 9-36 V supply, IP67, CAN bus |
|---|---|
| PWM tip driver | 12 V, 16 control channels |
| Frequency | 1 Hz - 1 kHz, adjustable (typically 20 Hz) |
| Capacity | Independent control of up to 160 nozzles |
| Pressure signal | 0-10 V or 0-20 mA |
| Flow signal | 0-10 kHz |
| Nozzle mount | 3/4″ standard |
Will it suit your sprayer?
Send us your boom width, nozzle spacing and current setup and we will work out the fit and the cost.