question

ruud avatar image
ruud asked

MPPT 150/45 maxing out at about 2400W

Setup:

- 48V system
- Lynx distributor
- Lynx shunt
- Cerbo GX
- MP II / 5000

- 10x 450Wp panels 2S5P

- Storage 30kWh


It seems the MPPT will not accept more than about 2400W (showing about 90-91V, 27-28A). When suddenly clouds move or reflection drive up the input to 2600 - 2700W the MPPT resets completely.


For me this is unexpected since both voltage (150) and amps (45) were never reached. Removing some panels and diverting them to another system with separate MPPT's the total collected Watts jump up to > 4200W.


Why does the MPPT never reach the specified limits 150/45 untils it resets?

MPPT Controllers
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2 Answers
nickdb avatar image
nickdb answered ·

What's your battery voltage? Power is determined by that. 2400W is 53.3V at 45A which seems about right.

PV voltage is determined by the panels, load and irradiance but the current rating is on the battery end.


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ruud avatar image ruud commented ·
Ahh... I recorded the battery power at these moments, 53.42V. That's my bad, I expected the 45A being the solar input...
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kevgermany answered ·

The 45 in the model number is the max output current. 2400W @ 45A is 53V, about right for charging a 48V system.

I think you're mixing up input and output specs.

In any case you need either a bigger MPPT or a second one.

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ruud avatar image ruud commented ·
All clear now as explained above. Yes I definitely need an extra MPPT.
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