Installation manual

8.3.2. Cutting the jets to correct size

The plastic tapering jets can be cut on site with a sharp knife. The jets are inexpensive so a

trial and error approach can quickly determine the correct jet size. It is important to cut your

jet to the correct size cleanly so that the water jet can break smoothly without spray. We

recommend using a sharp knife and paring away at the jet, cutting from the inside edge out.

With practice a very accurate and sharp edged jet can be prepared in the field. The taper

gauge and knife supplied in the optional PLT tool kit helps to make this task easy.

Holding the plastic jet within a spare holder sleeve and end cap will ensure the

jet is held firmly while you cut it to size. Take care as it is easy to slip, which

could result in a significant flesh wound. If you have Kevlar gloves, wear them.

Cutting the jet to size and checking it with the taper gauge

If you have plenty of water and want to generate the most amount of power that your

pipeline can deliver (before pipe friction chokes the output power) you should set the jet size

so that the pressure on the gauge drops to 2/3 of the static pressure.

This will only increase power output as your turbine is generating less than its nameplate

rating. Also note that you could have problems if the operating pressure is taken down much

below the value calculated in the original system design. It may no longer be possible to

optimise turbine speed whilst staying within the acceptable output voltage range,