isolators Image


GALVANIC ISOLATOR, VDI-16 A or 32 A for 115V

I'm replacing a galvanic isolator on a 115V / 30A shore power line. I would like to use a Victron product, but the specs are only provided for 230V. Would these units work on 115V and would I use the unit spec'd for 16A / 230V or 32A / 230V? Doing the math, the wattage equivalent is 16A / 230V, but I am unsure if this is the correct way to determine equivalence in an a device with diodes, etc.

Dan Gabier asked

0 Answers

Using an Orion 12/12 30A Isolated with an Existing Isolator?

I am in the process of switching out an AGM 400ah battery bank on a sailboat with LIFEPO4. I have already purchased the Orion 12/12 30A Isolated equipment to protect the alternator and ensure correct charging parameters supplied to the LIFEPO4.

Question - while planning the installation, I am thinking the best option is to simply wire the 'house' output of an existing isolator (manual here: as the input to the Orion. Second output of the existing isolator will remain the same and go to the existing 100ah AGM starter battery. Any issues with doing this?

lwitty asked
lwitty commented ·

1 Answer

Victron 160A Argo Diode Two Battery Isolator using charger instead of alternator

The application is on my sailboat using LiFeP04 batteries.

1. Can I use a Victron 160A Argo Diode Two Battery Isolator with a 160A charger instead of an alternator?

2. I have two battery banks that I want to isolate. One has two 300A batteries and one has one 300A battery.

3. Would the proper wiring be the cable from the charger goes to the input stud of the Isolator and then two cables on one output stud goes to each of the batteries in the bank with two batteries and then another cable going from the other output stud to the bank with one battery?

3. Each bank goes to a Bat1/Bat2/Both/Off switch and then to the load.


allen-in-panama asked
allen-in-panama commented ·

0 Answers

Cyrix-i 400A as a battery isolator.

Hello everybody,

I was wondering if it is possible to use the cyrix-i 400A as a battery isolator, by activating/deactivationg the Start Assist switch.
Obviously on the battery 2 contact there will be no battery, but only the load.

maurizio-menghini asked

0 Answers

Replace Sure Power Isolator model 1202

I am replacing a Sure Power model 1202, which has failed, with a Victron 120-2AC .

The Sure Power unit does not have compensation conections but the Victron does.

For a straight swap can I simply connect the inputs and outputs as per the current Sure Power unit and make no connection to the Victron's compensation connections? In other words, simply not use the Victron's compensation connections?

gary123 asked

0 Answers

Victron Galvanic Isolator ABYC compliant

Good afternoon,

Does anyone know if these units are ABYC A-28 compliant fail-safe design? I see the question was asked a few months back, but no direct answer to the question.

dgulliver asked
mike-g edited ·

1 Answer

Does my proposed use of Victron 3-200 Argofet Isolator make sense?

I am planning to install the Victron Argofet 3-200 Isolator in my forbie to provide charge for my Starter and two Auxiliary batteries. Each of the batteries is of a different type, the starter is your typical wet cell albeit an ultra performance Century, the Aux1 battery also under the hood is an AGM and the battery in the rear is going to be a LiFePO4.

I of course want to make sure the Starter battery takes priority and isn't drained by all the devices powerd by the other two Aux batteries and I believe this is exactly what an isolator does.

Next, I want the Aux 2 battery in the cargo to get the best charge (highest voltage and current) which i assume the CTEK Dual 250S and Smartpass will hopefully take care of ie make up for any voltage drop resulting from length of cable from the front under bonnet to the rear cargo as well as getting up to 120Amps into the Aux 2 battery (dependant on input which is unlikely to be anywhere near that dependant on charge of other batteries and alternator output so probably overkill but i wanted to make sure these weren't the limiting factor).

The Aux 1 battery under the bonnext just provides additional power for the UHF radio etc and has a momentary switch plumbed in to join it with the starter in case the starter does actually die.

I also plan to attach the Victron phoenix 12/1200 inverter to the LiFePO4 battery for 240v,

Anyway my question is... Is the use of the Victron Argofet Isolator in this configuration sensible? I thought it looked ok but I have read that it may not be ideal due to there being three different battery types and capacities which may result in the starter not getting a full charge or even eventually going flat when using the Victron isolator in this way.

For clarity in demonstrating my setup I have excluded from the diagram, all fuses and circuit breakers which have been used extensively at both ends.


the-tango asked
the-tango edited ·

1 Answer

Should I use 3 separate 2-pole breakers or a 3 pole breaker for a 3 phase grid?

I'm planning to make a 3 phase system with 3 Quattro 5kVa and I'm wondering how I should set my breaker for the 3 inputs from the grid.

Should I put them separately with 3 dual pole breakers or just put them all on a single 3-pole breaker. The three pole breaker would cut off everything when tripped but having separate breakers would mean only one line of load would be disconnected if ever which I think is better. Most of the loads are single phase but would having 1 phase of the grid disconnected have a negative impact on the system? Thank you!

ylric asked
Paul B edited ·

1 Answer

MPPT 75/15 isolator when not in use ?


I am installing an MPPT 75/15 in a caravan, with folding plug-in solar cells.

I am concerned that if the caravan is not used for 3 months then the 75/15 will drain the battery since it seems to consume 20mA when not in use. I have an isolator for the load side. Do I therefore need to install a separate isolator for the battery to prevent drain ?

Or can I just install a battery side isolator which will also act as an isolator for the load side (even when solar panels are plugged in).


dfcremer asked

0 Answers

Multiple questions about the FET Isolator

I'm getting ready to install an Argo FET Battery Isolator - 200AMP/2 Batteries on my 20' pleasure boat and I have a few questions.

1. Because the batteries straddle the engine in the rear of the boat and require fairly short cable runs that can be secured is there any reason to install fuses in the lines? Currently the boat has no fuses to the alternator or starter or 1/2/Combine switch. If I need to install fuses what size would you recommend? I'm installing 2 awg wire and the current alternator is 55 amp with cable runs less than 10 ft.

2. Does the Isolator get too hot to mount directly to the fiberglass?

3. I currently have a 55 amp alternator but because I plan to install some stereo amps there is a possibility of up-sizing the alternator in the future. With this in mind I ordered the 200 amp unit rather than the 100 amp unit. Is there a downside to being over-sized?

Thanks for any advice you can provide.

casey-pries asked
casey-pries commented ·

1 Answer

Is the VDI-32 galvanic isolator a failsafe design?

Does the VDI-32 meet the ABYC A-28 standard and continue to provide a ground path even if one or both diodes have failed?

mike-g asked
mike-g answered ·

2 Answers

If Victron Energy Argo FET Battery Isolator always drawing power?

Does this device use any power when idle? I am leaving my sailboat at the can sometimes for a month. If it always drawing power, additional switch might be required to disconnect it from the battery. Otherwise I might find batteries on my boat dead when I am back. Please advice.

victorloddy asked

0 Answers

1 Answer

AGROfet isolator not behaving correctly


We tried with multiple Agrofet isolators and we observed the following: Battery connected to one of the outputs, there is measurable voltage on the input and output2. Is this normal? what is the reason for this?


eliott asked
Justin Cook - Bay Marine Supply USA answered ·

1 Answer

Can we use a three ways Argo Diode Battery Isolators with only two batteries ?

I've got a Victron Energy Argo 100-3AC ARG100301000R and I wish to use it before the installation of the third battery

yrreiht62 asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

Argo Diode Battery Isolators-voltage drop-AGM(14,4V) Bat-Charger sett on 14,8V


I want to instal the Argo diode battery isolator 80-2 SC between the Engine Batery (115AH) and House-Batery (2x110 Ah in Paralel) on a Sailboat.

Charging from an alternator....The compenstaion-diode will increas the output voltage as a compensation for the voltage drop of the Argo diode battery isolator 80-2 far all clear.

The Sterling Shore-Power charger have no Comp-outputt for the compansation cable. And have only 2 output-settings:

AGM Bateries=14,4 V

Lead Accid=14,8 V

voltage drop of the Argo diode battery isolator 80-2 SC is approximately 0,3 V - 0,45 V.

Is it OK to set the chager on 14,8 V ...and after the diode, there sholuld be 14,4!?!?

Or just be practical...mesure the inputt by each of the settings and then choose.

Thank you.

chiefsen asked
Justin Cook - Bay Marine Supply USA commented ·

2 Answers

Isolated DC-DC Converter to offer Lightning Protection to Navigation Electronic

Some years ago, my yacht had a 'little' lightning strike, and the effect to my complicated electronics was extensive. I am an EE, so I have fixed most of the items myself, and made an interesting project out of it!

My observation was that the ground side of the power input circuit was the only damaged item on the sensitive electronic items (B&G displays, NMEA multiplexor, fridge controller, almost anything with a status LED, etc.) A change of the input diode or regulator fixed many things.

I don't want to start a debate about protecting a boat from lightning, as I think it is pretty much impossible. But I can confirm that I have a heavy copper connection from my keel-stepped mast to my lead keel.

Now that I am re-wiring to accommodate my lovely LFP batteries and new Victron system, I am considering adding an isolated DC-DC converter to a small 12V battery to drive all the electronics. My main objective would be to have a "floating earth" for that separate system.

I am hoping that the DC-DC converter would die 'when' I next get struck, and it would save all the other electronics.

Would this be a likely case? I don't expect any guaranties, but wondered if anyone could comment that this is a possible path to go. Given that I am redoing all the wiring it is not a big issue to isolate the "Electronics GND wire"

Thanks for your thoughts..

andyalford asked
andyalford commented ·

1 Answer

Isolation of MPPT solar chargers

Isolation of MPPT solar chargers

No isolation between PV input and DC output

Basic isolation between input/output and chassis.

This statement is rather brief and unclear to me. Can anyone elaborate?



glenn-matthiesen asked
glenn-matthiesen commented ·

1 Answer

Using a Cyrix-ct 12/24-230, for 2 different battery banks

Hi All. The scenario is as follows:

We currently have a Cyrix-ct 12/24-230 connected in a Toyota Land Cruiser 79. This Cyrix charges the batteries in a caravan being towed (Via Brad Harrison connectors on caravan A-Frame). This works perfectly.

We now have a second bank of batteries in the back of the Land Crusier (2 x 125Ah). These power fridges in the back of the Land Cruiser.

Can the charging power of the Cyrix be split to charge the Land Cruiser's 2 batteries AND the caravan batteries (2 x 230Ah) simultaneously.... I have Argofet isolators available as well that can be fitted, if this solves the problem...


matt-rsa asked
Martijn Coster (Victron Energy Staff) answered ·

1 Answer

Can the BMV 712 relay be programmed to operate on temperature?

The BVM 712 has a temperature option. And it can also monitor battery voltage. Can the relay in the BVM be programmed to force Victron Isolator to isolate battery on temperature and voltage?

rvsolartech asked
boekel answered ·

1 Answer

How to power down the Victron Energy Isolation tranformer?

I have some welding to do on my steel boat. I know it is important to disconnect the batteries during welding. (no idea why). So, I ask now if it is also important to shut down the isolator - how to power down the Victron Energy Isolation tranformer?

sigrid asked
kai answered ·

1 Answer

12V House power and 24V PV Charger and Inverter.

I'm in process of scaling up my Motorhome power solution. Right now, it is 1200 watts solar to four 6V agm batteries in series/parallel 12V configuration.

My Idea is to rewire the battery to series 24V and charge from MPPT from solar. I would like to purchase a 24V Phoenix inverter, but at the same time keep the 12V House DC and Alternator 12V charging.

I'm about maxed out at 12V on solar and see the benefits of going to 24V, as I have room to add 600 more watts. My controller will handle 1800 Watts at 24V output with no issue.

Is it practical to tap off two 6V batteries to run the coach 12V DC portion (not much current is used, lights and water pump, etc) and keep the alternator charging @12V but use solar to series charge the bank @ 24V from the MPPT controller and pull 24V to the inverter? I know several suggest DC24V-DC12V converters and I have looked at Equalizers too. My concern is the alternator charging just half the bank and what implications that, if any, will have to the whole system. Perhaps some isolators of some kind would be needed here? The reason for all this mess is I'm sizing all this for the future when I upgrade to expensive lithium. I want it all to be at 24V for the inverter portion but don't want to trash the new AGM batteries at this point.

Actually, when charging with the alternator @12V to half the bank, Solar will also be charging @24V to the whole bank via the MPPT... If that is even possible without causing Cherrnobyl.

Educated thoughts on this are welcome. I have exhausted all my searches and asked The Google for optons.

dishusa asked
dishusa commented ·

4 Answers

DC isolators in larger BYD systems

Hi im designing a system with 2 parralell Quattro 15kW inverters linked to BYD pro batteries would you add DC isolators in between each of the batteries and the inverters? Doesnt seem to show them in schematics only fuses, im going to be using the lynx in, and lynx distributer so there will be individual fuses for each battery in and each inverter out. Thanks

jacko asked
JohnC answered ·

2 Answers


24 Posts
39 Users
1 Follower

Topic Experts

0 Points