Variable rate made simple, just follow directions

Capstan N-Ject | System makes it easier for farmers intimidated by
 variable rate technology to match map data with fertilizer injection rates

Adopting variable rate technology can be frustrating, especially transforming prescription map data into product that is injected into the soil.

The more hoops the data jumps through, the more difficult it be-comes, and the greater the odds of a miserable and frustrating spring.

However, an injection system that obediently follows instructions can simplify that challenge, said Garnet Welykholowa, a Capstan Ag Systems representative from Craven, Sask.

He said many producers are ready to get into variable rate, but the technology is intimidating.

“These are the guys buying the large new generation drills designed to be compatible with variable rate,” he said.

“And they’re all buying with the intent to go variable rate, but maybe just not quite yet. These are the guys showing the most interest in the Capstan N-Ject systems.”

Welykholowa said the Capstan Pulse Width Modulation solenoid removes barriers between prescription maps and actual fertilizer injection.

“The solenoid is either on or off, so product either flows or does not flow. There’s no in between and there’s no variation in the size of the orifice,” he said.

“With Pulse Width Modulation, the duration of the pulse, or the time that the solenoid is on, depends on signals from the controller.

“You never change orifices or nozzles. Controlling pulse width means you can vary the rate of product in a range of 25:1. That means there’s no need to get out of the cab to waste time changing orifices.”

The 25:1 range applies to the N-Ject for anhydrous ammonia and for the N-Ject LF for liquid fertilizer.

Welykholowa said Pulse Width Modulation appeals to more than just the variable rate crowd. Section control is the other main benefit.

Wider drills are driving the need for sectional control. Overlap in the headlands or around potholes wasn’t critical with 40 foot drills but becomes a major efficiency factor in 60 to 90 foot drills. Welykholowa said some drills now have as many as eight sections.

He said the N-Ject for anhydrous ammonia functions in much the same way as the N-Ject LF for liquid fertilizers. Product comes through the block, metered by the valve, and then travels to the shank.

“If the controller suddenly calls for section one to be off, the N-Ject closes all solenoids for that section. It takes 1.2 seconds before the anhydrous stops flowing out that shank. So that’s pretty close to being instantaneous.

“With NH3, the system pulses three times every second, so when you talk about variable rate and precision, it is very precise. And it’s pretty quick.”

Capstan says the flow of anhydrous in the N-Ject and the flow of liquid fertilizer in the N-Ject LF is retained in the lines all the way down to the knives so that there is instantaneous flow when the solenoids are triggered.

Welykholowa used the example of a farmer applying 25 gallons of product per acre at five m.p.h.

“The prescription map suddenly calls for 40 gallons. Here’s what happens with the N-Ject LF,” he said.

“The Pulse Width Modulation system gets the signal and increases the length of the pulses, so 40 gallons now go down.”

Welykholowa said some people don’t understand the Pulse Width Modulation concept.

“There’s an idea out there that we change the number of pulses per second. That’s false. We only change the length of each pulse. The normal pulse length is 3/10 of one second. We can control that to make the pulse longer or shorter. That’s how we control the rate so precisely.”

For more information, contact Welykholowa at 306- 527-1384 or visit .

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