Hello Community,
I want to run a swim-spa offgrid on Victron Inverters.
The sellers specifications for the swim-spa are:
4 massage pumps each 2,2kW
1 filtration pump 250W
Full Flow Electric Heater 3kW
All together 12,05kW.
Requird input: 380V-20A
The idea is to use 3 Multiplus-II 48/5000 in 3 phase mode.
Since pumps and heaters have a high starting current I'm wondering if this set-up will be enough?
I hope you can give me advise. Thank you very much!
Hello, If pumps are switched on in uncontrolled manner I would say no that not enough inverter power. If you can control that only one pump start at the time that would work. Anyhow I suggest detailed calculation for basis or double your inverters.
Also battery bank capability to push high inrush current in continuous cyclic manner need to be revised. If pumps are cycling on and off in short cycles that can lead over heating of components. Resistive heating is good to have as base load in case inductive loads present as well.
Thank you very much for the information.
I haven't thought about the pulsating pumps...mhm
Considering the starting current the new set up would look like this:
3x Multiplus-II 48/8000 in 3 phase
Either 4 or 6 Pylontech US5000
The Pylontech Batteries have a recommended discharge current of 75A and for up to 15min 120A.
Each Multiplus can have a permanent output of 6400W -> 19200W.
19200W/48V=400A
400A / 75A per Batterie would be 5,3 Batteries.
Regarding costs I'd like to use only 4.
Do you think the Pylontech Batteries could handel pulsating pumps?
Also as far as I understand it, the pumps are not running in 3phase since it's also possible to install a single phase .
This is all information I have and sadly I don't get more from them:
@NLS You might want to calculate how much energy it is going to take to heat 7.5 ton of water to your comfort level.
To heat 7500 liter of water from 15c to 45c will take 264 kWh.
7500 x 4 x 30 / 3412 = 264 kWh. Nearly 90 hours with a 3kW heating element.
Add 90 hours to run the heat / filter pump @ 0.25 kW adds another 22.5 kWh of energy.
Pretty close to 300 kWh of energy to heat your spa.
Your going to need a bigger battery....
So as far as I understand it is that they don't really want to use the heater. The location is Portugal and they only use it in summer when the pool is heated up by the sun anyways...
So forget the heating. It's more about the rest. The pumps/jets
And they only want to run it for 1 or max. 2 hours a day while the sun is shining.
On top the whole system will have 6000Wp Solar Panels running over a Victron MPPT 250/100
I wonder if the pulsating pumps effect the batteries in a negative way. But considering electric cars and other areas of application LiFePo4 should work for this setup. What do you think?
