PowerSpout
TRG installation 2018
Last revised July 2018
© 2018 EcoInnovation Ltd (NZ)
Page 32
Do not operate the turbine connected to any MPPT controller or Grid-tie inverter without first
checking and adjusting the open circuit voltage (Voc) as described below! If the voltage is
too high then your controller or inverter will be destroyed and there is no warranty for this.
Take a photo of the turbine identification plate for your records. Verify that the water
pressure is as stated on the plate. If the water pressure is much different then you should
find and fix the cause, because otherwise you will need a different stator supplied.
Checking the open circuit voltage (Voc)
You must check the Voc prior to connecting your MPPT or GTI, because
excessive voltage will damage connected equipment. Connect the output
wiring to a multimeter (on its highest DCV range). Do not connect any other
equipment or wiring at this stage. Take great care that no person is exposed
to lethal voltages. Perhaps you can insert the probes of a multimeter into your
turbine circuit breaker in place of the transmission cable.
You may now open the turbine valves slowly until completely open. It will be faster and
noisier now than later when operating on load.
Adjust the pipe supports to fine-tune the jet alignment (to maximise the speed). Apply
downwards, upwards and sideways pressure to the jet to alter the angle slightly and see
what effect this has on output. The jet position can be moved slightly within the casing. Once
optimized, secure and support the pipe.
Check that the pressure is constant. If not, check that the intake has surplus overflow water.
If there is not enough water then the pressure will fall slowly as air enters the pipe. In that
case you may need to close some valve(s) or fit smaller jets before you can operate
continuously.
Observe and record the maximum open circuit voltage.
Confirm that measured Voc is at least 10V below 90% of the safe limit for your MPPT
controller or GT inverter. (This allows a margin for ripple in the voltage.)
