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Argo FET

Wire up boat electrics with two alternators using ArgoFet?

Hi All

I'm in the process of sorting wiring of my narrowboat. I've just added solar so would like it to be able to charge my leisure batteries (currently connected) and also my starter and bow thruster battery and this is where im getting a little confused. I have a leisure and a starter alternator which complicates things! I was thinking about using an ArgoFet to assist? does this look possible?


projectwaterlily asked
projectwaterlily answered ·

1 Answer

Charging 12 V and 24 V with the same system

Hi all.

I have a real technical challenge. My barge starter motor is 12 V (tapped from the centre of a 24 V battery pack). My domestic battery system is 24 V. Currently using a 24 V alternator and old Victron charger.

NB: The only reason the previous owner made this work is because both battery packs are connected for the 240V inverter and therefore avoided leaving a battery on the starter pack without a load.

I want to let the 12 V starter system remain but not tapped from a 24 V battery pack. I need to separate the two battery packs.

So to my question - - Using the Multiplus II and ARGOFET how can i charge 2 different voltage battery systems ?

Thank you for your help on this.


miltonmews asked
kevgermany commented ·

2 Answers

Voltage on input


With the isolators connected as drawn, I'm getting 8.4V on the input of each isolator with the engines off. I have disconnected the input of both isolators and measured voltage on both B+ cables coming from the alternators and they are basically 0V. The grounds from MNB to isolator are #14. With only the B+ input cables off, I measure 8.4V on the input stud. Is there anything I need to check? Any ideas?



soundguy asked
soundguy answered ·

5 Answers

ARGOFET alternator cable fusing

Should I FUSE the cable connection between the alternator B+ output and the Argofet Input ? On which side (close to alternator or close to argofet ?)

THe alternator has a rated output of 55A (Hitachi LR 155-20 for Yanmar) and the cable is 35mmq, than can carry all of the current. I don't believe there can be a fire risk on the cable, if there is a short on either side of the cable. May be the alternator can burn if it sees a short at the output, but I cant fuse less than 55A, and If I use a larger fuse I don't think there is much more short circuit current enough to blow a say 70A slow fuse.

ANy recommendation ?



abuonocore asked

0 Answers

Cyrix or FET diode bridge ?
Hi everybody,

I am in the process of upgrading my boat from a single battery to separate battery banks. I have a few questions about that.

1. what / which technology is best to use and connect to charge both banks with the chargers (shore power, alternator, wind and solar).
2. I have been looking for Cyrix and FET Diode bridges and do not know what is best and how to connect. And if a Diode is a 1 way system how do the chargers know when they are full.
3. What are the best universal settings for AGM batteries if I want to set the BMV712, Smartsolar and shore power charger. Now I notice that my old lead battery is not yet full according to the charger, but the BMV gives 100% and keeps bulking for 30min.

all tips and help welcome :)

greetings Ian



ian-macleod asked
morissen answered ·

1 Answer

Charging setup for LiFePo4 and Lead Acid: ArgoFET and/or Orion Tr Smart

I have three Lead Acid battery banks installed on my boat (house bank, starter battery, bow thruster battery) which are charged by the alternator (let's only focus on the alternator and ignore other chargers)

All three battery banks shall be strictly separated which is done with an ArgoFET (B+ --> ArgoFET --> 3 Battery banks).

Now I want to replace the house bank by a LiFePo4 battery. In order to protect the alternator from overheating I am planning to insert an Orion Tr Smart between the ArgoFET and the LiFePo4 battery. A great solution for me, because it's a minimal change in wiring.

In other forums I've read that this solution might not work out, because the hungry LiFePo4 will draw all the current from the alternator with the Lead Acid batteries left with next to nothing. What do you guys think, is this correct?

An alternative could be to connect the starter battery directly to the alternator, and to charge the LiFePo4 and the bow thruster (LA) battery via two separate Orions from there. But shouldn't the problem with the hungry LiFePo4 occur there as well?

Are there good reasons why this is the better setup? Well, for me it means more work and more cost.

Or is there another solution that is even better?



meester1-de asked
meester1-de 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
einar answered ·

1 Answer

Off grid installation with a 2. battery and ARGO Diode


I run an island system at home (currently with a 48V/120 AH LiFePo battery and a Smart Inverter 48V/3000W, as well as 9 solar panels with 150/35 Victron MPPTs).

Now I would like to integrate a 2nd battery pack 48V/50Ah with its own BMS.

That is, the charging current should come from the MPPTs, but no current should flow backwards to the inverter. I would like to supply a different circuit on this 2nd battery.

Could I interpose an Argo diode battery separator on the incoming side (from the MPPTs) and then connect the two batteries there?

The Argo diode battery separator is actually intended for the charging current from the alternator!

Thanks for helping

tbecks asked

0 Answers

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 ·

2 Answers

Argo input- What does MPPT see?

The barge had it's last upgrade in the 80's; electrical system is clean and very professional, 24vdc 220v ac. When originally set up, battery charging was done through inverter/charger either via shore power, generator or engine alternator (standard vehicle unit, nothing special). There are three banks, house, starter and bow thruster. Inverter/charger (MulitPlus Compact, new 2016) is wired to house bank with trickle charger to starting bank. Alternator is routed through old school (pre-FET) Argo with one input and three outputs (Argo model 1203, max amps 120, max charger amps 75). In the mid 2000's solar was grafted onto the system with the controller connected to the Argo on the input terminal with the alternator. Since the generator has given up the ghost I'm going to significantly upgrade the solar. All battery chemistries are currently similar although lithium is in the cards for the house bank in a few years.

Is this a good way to set this up? Is there a better way? What does the MPPT "see" when running, the starter battery and bt battery full and the house bank at 70%? When there is no alternator input?

bargeman asked
eien answered ·

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
eien answered ·

1 Answer

Argo FET 200-2 "leakage"

I have an Argo FET 200-2 in my boat. Separating my LifePo4 AUX battery bank from the AGM starter batteries. I am struggling with a small reverse current flow between the battery banks.

Is it correct to say that the Argo FET 200-2 may be "leaking" and will allow som reverse current if it is Energized and as long as there is no alternator current running to the Input terminal?

mmosberg asked
roly answered ·

1 Answer

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
eien edited ·

3 Answers

Cyrix-CT / Argofet Isolator with Supercapacitors

Hi, does anyone knows can a Cyrix-CT Battery Combiner or a Victron Argofet Battery Isolator be used to connect my w204 AGM starter battery and a pair of 100F Supercapacitors for my audio? My car has "Alternator Management" under my spec sheet.

If possible, which is preferred? Any advice will be greatly appreciated and thank you in advance.

Best Regards

davidw asked
davidw edited ·

0 Answers

230V Charger before Argofet 200-2 it works?

Argofet 200-2 and 230V charger, can you clamp the charger parallel to the alternator on the input of the Argofet and then charge both batteries with the alternator and the charger?

Background: If this works without problems, then I need a charger with only one output.

Greeting André

bugs-bunny asked
Trevor Bird answered ·

1 Answer

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