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Argo FET

ArgoFET and Voltage sense wire?


I have two battery banks, and want to separate them with a ArgoFET. My alternator has a voltage sense wire that i guess is used to measure the actual voltage as close to the battery as possible. To my understanding the regulator tries to keep the voltage as high as possible without cooking the battery. Where to I connect that wire? To the start battery, or the service bank?

andreholgersson asked
benm answered ·

1 Answer

Energize permanently

I would be grateful if you could tell me if the "Energize" terminal of the Argofet battery isolator can be permanently connected to positive.

eien asked
offroadflow commented ·

0 Answers

Alternator not charging with ARGOFET


I adopted my engine with an Argofet 200-2, so that I can charge 2 different battery packs. Unfortunately I can't install the Argofet as proposed in the specification, as the ignition switch and the resistor is integrated in my engine control unit.

As proposed in the Victron datasheet:


My System looks like this:


I know that my alternator needs dc voltage at B+, therefore I used the energize Input. Unfortunately this energize input doesn't work in my system and the alternator is not charging and producing voltage. Why has the resistor / lamp to be between Engergize Input and D+?

While testing I accidentaly interrupted the ground cabling from the Argofet. Funnily without ground, everything works fine, but I doubt that's the ideal solution.

Does anyone know how the ArgoFET looks like / works in detail and what could be the reason for the malfunction.

Thanks a lot


waibel asked
andreholgersson commented ·

1 Answer

borne energize

argofet plan2.PNG


J'aimerais comprendre. On dit que la borne "energize" fournit du courant à B+. Mais sur le plan on la branche sur D+. J'ai fait mon installation et mon Argofet branché sur mes batteries j'ai une lecture de tension sur la borne input donc indirectement sur B+. Je n'ai rien changé sur mon circuit D+. Le "sense " de mon alternateur a donc une référence.

On dit que la borne "energize est optionel. Pourquoi?


menagoesenog asked

0 Answers

Argo which terminal for Alternator sense?

Hi, I've installed Argo FET split charger to charge my starter and 2 (separate) LFP banks. The Balmar MC614 Regulator states to place the Alternator voltage sense wire onto the largest bank if using a split charger, so in my case that would be the 400ah LFP bank.

Just a little concerned that this will potentially expose my starter to too much current and force it into a high voltage state.

I did think that using the MC614 Batt temp sensor on the starter battery might help. Other option would be to place the sense wire onto the starter battery, but then would that not prevent the LFP banks from charging?

Hope someone with a better understanding of this can help.



stocksy asked
jwfrary answered ·

3 Answers

How to connect Smart solar MPPT 75/15 to an Argofet 100-3?

How to connect Smart solar MPPT 75/15 to an Argofet 100-3?

I have installed an Argofet to the 3 different batteries and would now like to install the Smart solar on the input of Argofet, is that possible or do I need to add some other device in between? If I only connect it to the input then will the MPPT be turned off.

ajforsberg asked

0 Answers

One more Argofet Isolator Question - Energize Optional?

As someone trying to install one of these isolators I have searched high and low to try and answer my question. Jeff from Yacht systems has multiple YouTube videos but seems to gloss over most of the important details of the install. I find Victron installation instructions bland and lacking in explanation making the diagram irrelevant for most real world boat applications.

The Isolator Negative and energize connections are shown simply and without advice on purpose or placement. Also there are several posts that discuss back-feeding issues; blowing fuses and funneling power through what is supposed to be only a low amperage circuit. There is very little description of what this circuit is doing inside the Argofet or the Argo Diode systems.

I am hopeful people that understand these can try to compile answers here for others to understand more easily as well as help my own situation.

My application: 2001 Chaparral 240 Signature single engine Mercruiser 5.0 w/ 70 amp alt (3 wire), two AGM group 31 Batts, 4 position switch, currently a 20 year old Guest diode isolator, and wired in typical fashion with the alternator B+ output to the starter post then back to the isolator and then batteries.


#1 On an application with a typical stock internally regulated mando, mercruiser, GM style alternator. How relevant are the energize inputs on these isolators in that setting? Victron manual states the Energize circuit is optional...

(seems it would be nice to keep it simple and avoid back-feeding issues by omitting the positive energize connection)

#2 If it is not used what will the unit not be able to accomplish? (will voltage drop be higher without?)

#3 Is anyone able to confirm that the energize circuit is truly only needed for older alternators that do not have a self excite, or an externally regulated alternator? (if truly optional who can omit?)

#4 If the Positive energize connection is needed... -

Diagrams show that it is spliced into the alternator Sense position. Will this not back-feed through the harness to other loads? I am assuming I can not simply wire this directly to my alternator and separate the sense (purple) from the rest of the harness. I would imagine that would disrupt an input to the PCM and confuse something important. It is hard to tell weather the isolator wants to output a voltage at the excite or input a voltage from the excite.

#5 Could someone clarify the purpose of separating the charge current path from the Isolators point of view. (remove daisy chain from alt to start, and wire direct to batt/isolator.)

I really hate the part in every video from Pacific yacht systems where the installer states "I am not going to go into details why".... but then elaborates on needless points the rest of the video, just adds to the mystery.

-Is this only to maximize the voltage and limit the drop through the multiple connections?

#6 Can the same answers be applied to the ArgoDiode series of isolators?

Thank you to anyone who is able to contribute.

Photo shows Victron suggested install diagram. D+(61) = energize circuit


mcroni19 asked

0 Answers

Torque for ARGO FET M8 bolts

Anyone who has information about recommended torque for 8mm bolts on ARGO FET?


0 Answers

Argo FET for 2 alternators, 3 batteries

Replacing an old diode battery isolator here. The original was simple, with two inputs and 3 outputs.

Argo does not have a FET isolator with two inputs.

I was suggested to use two Argofet 100-3, and connect the outputs in parallel. I created a simple schematic of my understanding. Can someone with expertise on those boys to chime in?


jetkit asked
priba answered ·

2 Answers

Combine ARGO FET & Orion TR smart

Our current electrical installation on our sailboat has the following setup: 115Amp Alternator which is feeding the starter battery and the service battery bank through an ARGO FET Diode. The ARGO FET prevents back feeding the starter and service batteries vise versa. Know I plan to upgrade my service batteries with Lithium batteries. This leads to an charging upgrade and I plan to use two Orion TR smart 12/12-30 in parallel. Can I install the two chargers behind the already existing ARGO FET on the used output for the service batteries or should / can I remove the ARGO FET and replace his functionalities with the two Orion TR smart? Below the current installation:


The question is only focused on the ARGO FET and the Orion TR smart. The Lithium Upgrade will contain several additional changes regarding: BMS, smart Battery Protect and so on.


mzurkirchen asked
Sarah answered ·

1 Answer

Akkuspanning valt ineens weg van 24,5V naar 19V. Als ik de inverteren uitschakel gaat de spanning weer terug naar boven de 24 volt zonder dat het paneel stroom maakt

2x Gel akku 120Ah, Mppt 100 | 30 Smart solar, 1 paneel 270Wp, Phoenix inverter compact 24 | 2000. De akkuspanning valt ook weg als er geen stroom gebruikt wordt en allen de inverteren aanstaat. Het meest vreemde is dat de akkuspanning zich weer hersteld zonder dat de akku's worden opgeladen. Ook het ineens wegvallen van de spanning doet mij vermoeden dat de akku's niet leeg zijn maar dat het systeem een fout maakt. Het gebeurd trouwens wel alleen bij slecht weer als het paneel weinig tot geen stroom produceert.

mattveen asked
erikkater answered ·

1 Answer

Charging LiFePO4 with Alternator and Diode

I have an existing system with a starter battery (12V AGM 100Ah), a bow thuster battery (12V AGM 280Ah) and a new service battery bank (12V LiFePO4 560Ah with REC Smart BMS). Additionally this will be charged via Victron Multiplus using shore power or a VICTRON MPPT solar charge controller (only for the service battery bank) or it all can be charged by an alternator, which is connected via a diode (VICTRON ARGOFET 200-3) to all three batteries.

The old system was quite simple as usual in yachts, as the alternator just charges as the service battery tells him, how much more can be charged.

Now with LiFePO4 I read this should be charged via DC-DC charger from the starter battery.

Is this really necessary or cannot the ARGOFET still make sure the LiFePO4 batteries are charged by the alternator, especially since the SmartBMS will shut down the loading process, as soon as there is bad voltage/current coming to the system?

DC-DC chargers only deliver up to 30A and charging a 560Ah battery bank from a 100Ah starter battery seems unlogical, especially using a 130Ah alternator.

Is there something to make sure, if I want to charge the LiFePO4 directly from the ARGOFET?

Thanks for the feedback...


Marcus asked
bathnm commented ·

5 Answers

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