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MPPT Charge controller.


vulgrim

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The best in my opinion is the Victron 150/85, and I say this not only because I'm a Victron fan boy. I've seen what they look like inside, seriously upmarket construction and quality. Only problem is, 85 amps is the largest one they make, so you'll have to go with two 150/70 units, but you're talking around 30k at the present exchange rate for two of those. The 150/70 is arguably even better. No fans... completely natural convection.

 

The only other units I have experience with, are the Microcare units. I believe they do make a 100A unit. I also heard their quality have improved lately. Will set you back around 10k. I won't say this is the best though.

 

I have no experience with some of the other upmarket units, such as the Morningstar or the Outback. From what I've heard, very good, and very expensive.

Edit: You can get two 100/50 or three 100/30 units for much less. And as someone who has lost an MPPT controller, having more than one makes a lot of sense... :-)

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Value for money is certainly the combination of a pure sine wave inverter with built-in MPPT controllers like the hybrid Axpert/PIP 4,000w 5,000 Va. It has a 60A MPPT

charging controller and an intelligent 60A mains charger, totalling 120A charging. You can also go the grid tied way with a KACO 6002. This unit is far superior but only works grid tied without batteries. It will deliver 6,000w with MPPT range starting from 200v - 510v. Brilliant unit if the purpose is to use and save shore power whilst the sun is shining.

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Reason I ask is that, looking quickly, neither Victron (as per Plonkster), Outback nor Morningstar go that high.

Reasoning is simple I suppose: It gets really difficult to make it work safely.But, you could use more than one controller, depending on what you want to do.

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Reason I ask is that, looking quickly, neither Victron (as per Plonkster), Outback nor Morningstar go that high.

Reasoning is simple I suppose: It gets really difficult to make it work safely.But, you could use more than one controller, depending on what you want to do.

It has to do with the construction of the Buck converter that is the heart of an mppt. At those currents, you need big inductors... or higher frequencies, and then there's skin effect at the higher frequencies, so moral of that story is that it gets really difficult to do high voltage high current efficiently. It's much better to use a few smaller ones. And that brings to the topic of using interleaving with multiple smaller inductors in a single mppt... but that's a different topic :-)

Sent from my GT-I9195 using Tapatalk

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2 hours ago, plonkster said:

It has to do with the construction of the Buck converter that is the heart of an mppt. At those currents, you need big inductors... or higher frequencies, and then there's skin effect at the higher frequencies, so moral of that story is that it gets really difficult to do high voltage high current efficiently. It's much better to use a few smaller ones. And that brings to the topic of using interleaving with multiple smaller inductors in a single mppt... but that's a different topic :-)

Sent from my GT-I9195 using Tapatalk

If you use a few smaller units, and you can afford it, make sure you have at least 2/3 capacity left if one MPPT is taken out of the equitation. 

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I just realised something. Many of the smaller Victron MPPTs cannot go up to 48V. You may literally have to choose between the 100A Microcare and two of the large Victron units. The Victron is just so much better quality, but man... the price!

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Vulgrim, before advice and ideas can be shared, we need more info.

  1. What system do you currently have?
  2. What make and model panels, how many?
  3. How many panels do you need / want? 
  4. Home / Business?
  5. Grid tie or Off-grid?
  6. What is the load you want powered and for how long, at night, if you have batteries?

To increase panels on solar charge controllers is no problem at all, if you do it right. ;)

Panels can be connect in series / parallel combinations so the big controllers can handle a substantial amount of panels, depending on panel watts and volts.

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Okay the only reason for me wanting a 100 amp mppt is to increase the panel watts on my roof. So do i understand correctly i can use multiple mppt controllers on the same battery bank? 

I am running a 5kw Axpert 48 v inverter. Got 10 Benq 330 watt panels (3300watt)   (Voc :647  ,Vmp:54,7 volt and 7 Imp) 2 in series ,5 strings (parrelell). Got 8 Shoto AGM gel 150 amp batteries. No problem running during the night ,but daytime i dont want to use a combination of panels and batteries. Already got a Apollo 300L solar geyser and a gas stove. 

I would like to put 5000 watt on the roof.

Edited by vulgrim
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Found this on the net the site is WRND Engineering.                   WRND 48/120 for R5999
Specs.

WRND has a wide range of MPPT type solar charge controllers to best fit your needs. We manufacture in-house and support directly in South Africa. No need to pay the importers and expensive oversees shipping cost or waiting for stock. We offer a 2 year warranty as standard on our ProSeries products , but also have a 5 year and 10 year optional extension available.

MPPT solar charge controllers have been proven to offer far better performance compared to standard PWM type solar regulators. On average one can expect up to 30% better yields. This is because of the dynamic and intelligent way in which these controllers find and track the maximum power delivery point of the connected solar panels, hens the abbreviation MPPT (Maximum Power Point Tracking).

Given 30% better power yield translates to a significant cost saving when buying solar panels, one simple need less total panel watts to yield the same average power output compared to a PWM type solar regulator. In addition, the MPPT also log statistics, intelligently charges and conditions the batteries and can be user configured for optimum system performance.

Our units are all solid state and have no moving parts or fans that could malfunction with time. We also offer an optional conformal coating to prevent moisture from influencing or damaging the unit. This option is ideal for maritime applications, harsh environments, preventing damage due to insects and damp conditions.


Nominal battery voltage: 12V, 24V, 36V or 48V (auto select)
Handles panels up to: 6000W (48V system), 4500W (36V system), 3000W (24V system), 1500W (12V system)
Max panel voltage: 150V
Max continues battery charging current: 123A (electronically limited)

Charging (3 stages): Bulk, Absorb & Equalize
Log history: last 31 days (saves: kWh, run time and max pv watts)
Totals counter: days & kWh

Protection:
Over current protection in hardware and software
Over voltage limiting in hardware and software
Over temperature

Settings:
Charging current limit
Normal charging: voltage
Equalize charging: voltage, duration, occurrence

Other sizes available: 30A, 60A & 90A


Model: WMP4812A
Shipping Weight: 5.5kg



WRND MPPT big side.jpg

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I would not buy that.

Friend that works with me. He had 2 of them.

Posted in our Solar in Centurion group.

https://www.facebook.com/groups/818706591529524/

"This is a product warning. DO NOT buy a WRND charge controller. Both my 120amp WRND charge controllers died within 8 months."

He tried to get help and the dude just ignored him. They are made here in Cape Town I think.

 

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What viper said.

You cannot exceed the Axpert MPPT controllers limits and you cannot add another make and model controller to charge your bank. The controllers will debate too much on who is right.

So, when using more than one controller, the controllers must be identical, set to the exact same settings, as per Morningstar, or get controllers that can link together.

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3 hours ago, vulgrim said:

Yes I know I cannot exceed the mppt limit, all I am going to do is buy another Expert and run them in parallel.  Then each inverter can run from 3000 WATT panels on the roof. (120 AMP)

This is your safest bet and works exactly as expected. But make sure you balance the panels between the two inverters, i.e. 9 panels or 12 panels on easy axpert. They will share the battery bank. And make sure the firmware is the same on both. 

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6 minutes ago, vulgrim said:

Do you know of anybody who is running 2 Axperts in parallel?      So they use the same battery bank. But each will be running from there own pv array, and of course the communication cable must be installed between them.

yes

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23 minutes ago, vulgrim said:

Do you know of anybody who is running 2 Axperts in parallel?      So they use the same battery bank. But each will be running from there own pv array, and of course the communication cable must be installed between them.

My system works like that yes. 

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