The ideal rotation speed of the sprinkler is 1 R.P.M (Revolution Per Minute) with 60 arm beats per minute. This provides the crop with a consistent water supply. Excessive rotational speed reduces the distance of throw and the wetted diameter. Unnecessary arm beats lead to wear on the sprinkler arm and body and shorten sprinkler life. The Irrigation Systems Sprinkler has been engineered to provide optimum rotational speed and long sprinkler service life. For continued optimum rotation the sprinkler can be adjusted in two ways:

A) Spring Tension Adjustment
B) Arm Weights Selection

Tighter spring tension increases the number of beats per minute and speed of rotation.

Using the Adjustable 'Castle' Spring Tensioner, see Diagram:3:

(1) Clip the 'Castle' downwards, to disengage teeth.

(2) Rotate by one tooth to tighten or slacken the spring tension.

(3) Clip the 'Castle' back up into working position.

The ability to adjust the spring tension by hand is unique to the Irrigation Systems Ltd Impact Sprinkler. It is quick and easy to use in the field, although for day to day operation this would not usually be necessary.

Diagram: 3

Unique to the Irrigation Systems Sprinkler, the rotational speed of the sprinkler can be increased or decreased by balance weights inserted into the sprinkler arm. The number of weights vary according to the nozzle size

Four weights required with 5.5mm nozzle
Three weights required with 5.0mm nozzle
Two weights required with 4.5mm nozzle
One weight required with 4.0mm nozzle
No weights required with 3.5mm nozzle