Solar panel array in Series

[Sydneywizard]

This is a noob question but I cannot find the answer anywhere.

If I have 4 x 100W (12V) solar panels connected in Series, does that mean that I have a 48V array? My Renogy 40A MPPT solar controller is 12V/24V and I always assumed that it referred to the battery configuration and not the solar panel array but something someone said brought that into question.

I've always based my solar array vs solar controller calculations on Max Solar Input Voltage of the solar controller. Have I got it wrong? If so, I will need to change my config to S2P2 to not fry the controller.

 

[sunshine_eggo]

If I have 4 x 100W (12V) solar panels connected in Series, does that mean that I have a 48V array?

Sorta, but that's antiquated terminology. If you wanted to charge a 48V battery with those panels on a PWM controller that's what you'd need.

Depending on the type of panels, they may be close to 90Voc.

My Renogy 40A MPPT solar controller is 12V/24V and I always assumed that it referred to the battery configuration and not the solar panel array

That is correct.

but something someone said brought that into question.

"Something" is probably wrong/misinterpreted.

I've always based my solar array vs solar controller calculations on Max Solar Input Voltage of the solar controller. Have I got it wrong?

Array total Voc must not exceed the MPPT's PV input voltage limit in ANY conditions, i.e., you must also consider cold temperature effects on Voc.

 

[Hedges]

Equipment model numbers and links to data sheets help us help you.

This one says 95V

Rover Li 40 Amp MPPT Solar Charge Controller

Buy Renogy's Rover 40 Amp MPPT Solar Charge Controller. Pair it with our BT-1 the BT app through bluetooth and you can monitor and adjust your solar system directly from your phone. Our Rover also comes covered in a die-cast aluminum exterior. This allows for safe heat dissipation along with...

www.renogy.com

This one says Open Circuit Voltage: 24.3V

100 Watt 12 Volt Monocrystalline Solar Panel

Renogy 100 Watt 12 Volt Monocrystalline Solar Panel is one of the main components for any solar power (PV) system. Whether you plan to use the solar panel for seaside travels to the beach or your cabin in the mountains, this panel can be a great start or addition to any Renogy off-grid system!

www.renogy.com

So in the case of these two, three panels in series is the max. (and sufficient margin for cold weather.)
That would be 300W (STC).

SCC says Max. PV Input Power: 12V/520W, 24V/1040W
Consider 2s2p (400W) or 3s2p (600W) for 12V,
3s3p (900W) or 3s4p (1200W) for 24V

It is generally OK to overpanel a bit, not sure if Renogy is known for committing hara-kiri.
Under most conditions, panels put out less than STC rating.
I would orient some 3s strings differently, to catch morning and afternoon sun while reducing peak power.

But look up specs for your particular equipment.