Are FLEXmax 60/80 and FLEXmax 100 AFCI MPPT Charge Controllers?

Discussion about the FM100, FM80, and FM60 Charge Controllers

Moderators: OutBack, OutBack Moderator Team

Post Reply
Forum Junior Member
Posts: 1
Joined: Mon Mar 28, 2022 9:24 am

Are FLEXmax 60/80 and FLEXmax 100 AFCI MPPT Charge Controllers?

Post by AshleyRobin »

Currently I am looking for Charge Controllers. I tried using PWM Charge Controllers but it doesn't support the output device of the solar panels. I want to buy MPPT Charge Controllers, I see in Outback there are 2 outstanding products, FLEXmax 60/80 and FLEXmax 100 AFCI, so what type are they? Can you advise me?
Forum Emperor
Posts: 7743
Joined: Tue Jul 26, 2016 5:57 am
My RE system: Flexpower Two: (2) FXR3048A-01, (2) FM80, MATE3s, FlexNetDC
6 SimpliPhi 3.8-48 (48v @ 75AH. 450AH total)
Outback IBR3 battery enclosure
REC Alpha 440W panels - 2 arrays: each of 4 strings of 2 in series
Honda EU7000is gas fuel generator

Re: Are FLEXmax 60/80 and FLEXmax 100 AFCI MPPT Charge Controllers?

Post by raysun »

All the FlexMax are definitely MPPT charge controllers. They are rated at 60A, 80A, and 100A output current respectively.

The FM60/80 have been in the Outback lineup for many years, and can be used "stand alone" with batteries of 12 to 60 volts. The FM100 requires the addition of a Mate3s system controller to operate.

The FM60/80 can accept solar array string voltages to an absolute maximum of 150V. The FM100 absolute maximum of 300V.

Maximum array power handling depends on battery voltage. For example, the FM80 will accomodate:
12V x 80A ~ 1000 Watt array
24V x 80A ~ 2000 Watt array
48V x 80A ~ 4000 Watt array
Forum Emperor
Posts: 1020
Joined: Mon Jul 24, 2017 8:40 am
My RE system: 8330 watts in three strings, Flexmax 60 x 3, Radian 8048A, GSLC load center, Mate 3S, Hub 10.3, FN-DC and 900 Amp, 48V Trojan T105-RE battery bank.

Re: Are FLEXmax 60/80 and FLEXmax 100 AFCI MPPT Charge Controllers?

Post by pss »

Your question is very non specific. If you currently have any solar equipment, please complete your profile listing so contributors will be better able to assist you.
When purchasing a charge controller, you will need to size the voltage of your array as well as the amperage output of the array to the specification capacity of the charge controller. This will determine how many charge controllers you will need for your PV arrays. An MPPT charge controller is a product that contains build in software for maximizing the flow of current into the battery bank that the charge controller attaches into.

To help understand this, depending on the type of batteries you have in your bank, the voltage amount to charge them is to be specified, the duration of the different voltages (stages of charging) is to be input to the controller and the maximum amount of current that can safely flow into the batteries.

An MPPT controller will use this information to to take the amperage and voltage coming from the array and convert it into the optimal voltage and amperage to charge the batteries. In a flooded lead acid battery bank of 48 volts, the charging voltage should be about +18-24 volts over the 48 volts of the bank. If the array is sending 85 volts into the charge controller, the charger will reduce the output voltage and increase the output amperage to speed up the battery charging. And the calculation of the maximum power point can take place several times in a day if you like.

The Flexmax 60 and 80 have no built in rapid shutdown. You will have to add this on in compatibility with your inverter.

So the high efficiency of an MPPT controller lets you harvest more useable PV power and get it into your batteries.
Forum Guru
Posts: 233
Joined: Sat Apr 11, 2015 5:14 pm
My RE system: 7.9 kW self installed Enphase system NEM 2.0 PTO 9*2021. Skybox, and heat pump/AC system. The Skybox is powered by a 42 kWh pack of LFP batteries and 2kW panels. It will be used in self consumption mode for load shifting and backup.
Location: Kenwood, Northern California

Re: Are FLEXmax 60/80 and FLEXmax 100 AFCI MPPT Charge Controllers?

Post by Ampster »

There is a section for Charge Controllers. Why is this cluttering up the Skybox section? The Skybox has an integrated Charge Controller.
Drive Tesla Model X and Model 3 which are charged at Super Off Peak rates.
Post Reply