Installation manual

© 2014 EcoInnovation Ltd (NZ) Page 63
Operating Power
Voltage Watts
40 167
50 260
60 375
70 510
80 667
90 844
100 1042
110 1260
120 1500
Operating Power
Voltage Watts
80 167
90 211
100 260
110 315
120 375
130 440
140 510
150 586
160 667
170 753
180 844
190 940
200 1042
210 1148
220 1260
230 1378
240 1500
120V -1500W water elements
This is best illustrated by way of an example. Let us assume you
have a PLT40 turbine that is rated for 750W at 40 V. We want to
use a 120V 1500W water element as they are common in the USA.
The table shows the Wattage of the element in 10 volt increments
from 40-120 V.
As a PLT turbine will develop maximum power at about 40 VDC
MPPV we can set the PV trigger to operate at say 50 V. Once the
batteries no longer require all the 750W being generated the MPPT
controller will draw less current from the turbine, allowing the rpm
and incoming voltage to increase. At 50 VDC, the water element
will turn on and 260W will go to hot water heating.
Once the batteries are fully charged we might see the incoming voltage rise to 70 VDC and
510W will be diverted to the water heater.
If the incoming voltage is less than 50 VDC, all the available 750W will be going to the
batteries. Make sure the PV trigger voltage is at least 10 V above the MPPV.
240V -1500W water elements
This is also best illustrated by way of another example. Let us
assume you have a PLT80 turbine that is rated for 750W at 80 VDC
and you intend to use a Midnite Classic 250 VDC MPPT controller.
We want to use a 240V 1500W water element as they are common
globally.
The table shows the Wattage of the element in 10 volt increments
from 80-240 VDC.
As a PLT turbine will develop maximum power at about 80 VDC we
can set the PV trigger to operate at say 90V (note in a Midnite
Classic 250 the PV trigger function is called AUX - Diversion HI,
refer to 2014 Technical manual on how to set this up correctly).
Once the batteries no longer require all the 750W being generated
the MPPT controller will allow the incoming voltage to increase, this
will turn on the water element and at 90 VDC, 211W will go to hot
water heating.
Once the batteries are fully charged we might see the incoming
voltage rise to 140 VDC and 510W will be diverted to the water
heater.
If the incoming voltage is less than 90 vdc, all the available 750W will be going to the
batteries. The trigger point can be adjusted until a good result is achieved.