MWS System Components
MWS Single Line Diagram
MWS Installation Manual
Specifications of Elements and Thermostats – Please see calculations for expected system performance
All fixed resistive elements and thermostats are rated for connection to standard AC power., which is 230V with a sinewave frequency 50Hz.
Connecting to a fixed AC resistive element without a MPPT will result in efficiency being compromised by ±40% in good conditions this can decline to as much as 60-70% in poor overcast conditions.
Geyserwise has specifically designed the Geyserwise MWS with MPPT to effectively operate at maximum power efficiency of 99 % in the voltage range of 120 VDC to 350 VDC.
Use the below formula to calculate the PV array to best match the performance of MWS with different size heating elements.
P=Uvmp x Uvmp /R
R = (12 -17 or 27 Ohm)
2 Kw = 2000 watts with a resistance of 27 Ohm
3 Kw = 3000 watts with a resistance of 17 Ohm
4 Kw = 4000 watts with a resistance of 12 Ohm
If a 550-watt panel array is used with specification below:
550 Watts
41.7 Vmp
13.20 Amp
49.6 Voc.
The panel maximum current must be below 15 Amp.
Use a minimum of 3 panels in series
UVmp = 3 x 41.7 = 125.1
UVmp x Uvmp = 125.1 x 125.1 = 15650
On a 2 Kw element 15650/27 = 579 watts at peak.
On a 3 Kw element 15650/17 = 920 watts at peak.
On a 4 Kw element 15650/12 = 1304 watts at peak
The lower the resistance the better the performance.
Results of connecting four panels in series:
On 2 Kw element 27822/27 = 1030 watts at peak
On 3 Kw element 27822/17 = 1636 watts at peak.
On 4 Kw element 27822/12 = 2318 watts at peak.