[tedheath]

The system on my bus almost 15 years old it hasn't really degraded as it only ever put out 2.5 amps on a sunny day, so I will replace it. I have a 6A Leonics SPT series MPPT controller which I intend to keep. The amp meter is only 5 amps so I will uprate to a 10 amp one.
My question is say I see a 100 watt one then I guess thats about 6.5 amps which would cool but how much do they really put out flat in a clear sunny sky day.
Could I risk going to a 150 watt one without smoking my controller?

[scubadoo]

Expect 100W on a good summer day.
Most quality MPPT solar controllers will self current limit.
We have about 750-800W flat mounted and our Victron 50A controller limits at 50A or whatever lower limit I set.
Here is a screenshot of of our solar output at 4pm this afternoon here in Wellington between showers limited to 50A (c710W) by the regulator. I have observed 870W with a larger controller.

Click to enlarge.

[Paul]

Hi I would fit the largest panel that will fit and upgrade to a mppt controller ,there are some good deals out there . Paul

[Paul-Carter]

I put as many as I could fit on the roof, flexibles stuck down flat. I have not run the batteries down low yet to see just how much they will pump out. They are configured in two banks of 5 and even in overcast get up over 100 volts quite easily.

[tedheath]

Hi I would fit the largest panel that will fit and upgrade to a mppt controller ,there are some good deals out there . Paul

I have a MPMT controller its 15 years old and 6 amps does that mean its limited to 6 amps in or does it only churn out 6 amps?
6 amps going into the batteries is more than enough for my needs.

[Neddy]

Solar panel manufacturers specify the maximum current that can be expected from a panel in full sun. (Imp).

Ted, the manufacturers of that controller recommend a maximum solar input power of 80 watts. You could probably go to 100 watts without any problem, but I wouldn't go to 150 watts.

The overall power output of solar panels varies tremendously, depending on the time of year and the latitude. For example, a solar panel in Dunedin in Winter will provide just ⅙ the AmpHours of the same panel in Tauranga in Summer.

[tedheath]

Solar panel manufacturers specify the maximum current that can be expected from a panel in full sun. (Imp).

Ted, the manufacturers of that controller recommend a maximum solar input power of 80 watts. You could probably go to 100 watts without any problem, but I wouldn't go to 150 watts.

The overall power output of solar panels varies tremendously, depending on the time of year and the latitude. For example, a solar panel in Dunedin in Winter will provide just ⅙ the AmpHours of the same panel in Tauranga in Summer.

Thanks for that I will go a hundy W . To answer my question wouldnt a panel on an angle and facing the sun put out more ergs? so if its 80 W rating it would put out more than 80w if angled to the sun.
Does anyone how many % these panels are overated if flat?

[Neddy]

Manufacturers data is based on the sun's rays being at right angles to the solar panel. The more oblique this angle, the lower the panel output.