question

It's referring to battery voltage, not panel voltage.

MPPT 150/60 means:

150Voc maximum PV voltage in all instances (allow for cold temp effects)

60A output to battery, so max power depends on your battery voltage.

Victron MPPT are over-paneling tolerant. As long as you don't exceed 150Voc or the PV input current limit with array Isc (50A max on that unit), you're good.

Lastly, your array Vmp should be at least 1.5X nominal battery nominal voltage to ensure adequate voltage for charging.

Those ratings are for 12/24/36/48v charging voltages. The 150/60 can handle an array up to 150v and charge rates up to 60a

Oops. Snoobler beat me to it!

If you’re running a 12v battery bank you will not be able to realize the full potential of your array under perfect conditions

"Each panel is 36V and 5.15 Amp" Well that may be part of it, but it isn't the whole story and you need to be considering other factors...

Which Is I guess why you are asking, so treat that comment as an opening as opposed to a criticism, because that is how it is meant.

A PV panel is essentially a DC supply with a relatively high impedance. They are almost always specked at 3 important conditions...

Open circuit voltage...

This is what you will see if there is no current, for example when the battery is full or the grid is off, shutting down the PV charger/inverter, and there is even a modest amount of light.

Short circuit current...

All but self explanatory, the current you will see in optimal conditions with no load impedance, shorted.

Maximum Power Point, MPP or P Max...

The voltage and current at which the maximum power is delivered in optimal conditions.

A typical, 'nominal' 12V panel, in optimal conditions, will have a MPP voltage of circa 18V and an open circuit voltage of circa 21V. The current at any point, open, short or MPP, will of course depend on the panel size/area and will likely be the result of 150-250W / Sqr m depending on where you are, what panels you have and how they are aligned.

NB, Way less in most real world conditions, moderate cloud / light rain, 10% of that; at best!

Assuming your panels are essentially 3 12V cell arrangements in series...

Your OCV will be circa 63V so a string can only be two of those panels or you will exceed the 150V limit of the PV charger when it isn't doing anything, even in relatively low irradiance conditions.

Your system, assuming it has MPPT and is in full sun at exactly the correct elevation, on a cold day, would run at about 54V with all 6 in parallel so about 20.6A overall 1.11kW.

Using 3 strings of two panels in series will double the voltage, without stressing the PV charger in OC conditions, and half the current in your cabling, reducing cable cost and losses. 108V @ 10.3A

Depending on your virtual horizon and assuming ground mount, those same 3 strings, with added back-feed protection diodes could be arranged SE - S - SW with the S facing array at a much higher elevation. The Idea is to have the SE and SW biased arrays grab early and late light with the caveat that one of them is useless at either end of the day. however the low elevation makes the best of early and late light. The S array is then set at a much higher elevation to gibe it a longer window of operating. You are essentially flattening the curve, dial that in and it can be way better than a single orientation.

Have a look at some Solar predictors, Solcast is good, even an API, and free for none commercial use, but there are many to choose from. The important thing is to be able to specify the array characteristics so you can play with a virtual setup and compare options.

Hope that helps. Have fun and give ne a shout if you need specifics.

12V system. You'll get about 60A * 14.4V = 864W (or whatever the 12V rated output is).

You have 6 * 185W = 1110W of panels

You propose 6P arrangement with 33A Isc max. You are under the 50A limit on the controller.

130% is not a limit. It's a common recommendation as you won't miss out on that extra 30% most of the time as arrays rarely put out max power.

You are over-paneled (MPPT can't use all of the array power), but well within the allowances on the charge controller (150Voc max, 50A PV Isc max). Given that you are already concerned about shading (shading is typically devastating to PV yield no matter how the panels are arranged, but parallel is typically better), and 5 of these panels are flat on a roof, you will rarely be in a situation where the array will actually produce 1,110W.

I see no issues with the installation. Please be advised that most MC4 connectors are limited to 30A, so how you parallel them is important. You could parallel the 5 on the roof via MC4, but combining the ground panel with the roof array will need to be done in a combiner box. If you combine with MC4, recommend you install ONE 10A MC4 fuse on the (+) lead of each panel.

I am off grid, I don't use much power, generally, so a huge PV charger just necessary.

I absolutely agree that a huge array on a small charger is not generally a good plan, cost wise, but mobile and off grid is a specific use case.

Providing OCV and ISC are within spec, as stated earlier...

For some, not much, of the year the potential current/power will far exceed what the solar charger can deliver to the battery but the reality is that most of the time irradiance is far below max/optimal and over-paneled, in a conventional sense, is way cheaper than burning fuel in a generator.

The solar charger will just clip, as in, not deliver more than its design max current, and the PV voltage will float up as a result.

I have only ever looked at mine and do not know exactly why an ISC is specked where it is in any given unit.

I believe that ISC is the limiting factor, assuming appropriate string arrangement and thus OCV, when attempting to maximize the energy harvested in low irradiance conditions, and over-paneling to that end.

Are there other reasons no to do it?