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Lovato P2MB Double Pole MCB (P2MB2PC100) for Pylontech 48V isolation


Like a lot of people I am looking for a solution to the issue of isolating PylonTech 48V battery stacks. Looking on the victron videos on YouTube they show the Blue Sea 6006 or 9003 isolators with PylonTech, which while they are only rated to 48V DC I assume they are acceptable as they are shown in the official videos (I read somewhere they were actually tested to 72V).

While browsing I came across the Lovato P2MB Double Pole MCB C Curve 100A (P2MB2PC100) which based on the specifications will do 60V DC at 100 Amp. This is below the rated current for the PylonTech cables (120A) so would seem a good fit.

My plan is to have 6 stacks of 2 US3000C battery modules (all connected via the control cable to a Cerbo GX), with a positive and a negative cable to each pair (so 6 sets of cables going via the breakers to a pair of lynx power in modules and then to a lync distributor for connection to the inverter and mppts). Each pair of modules would go via an MCB (6 in total) so in the event of a fault I can isolate just that pair of modules and maintain the rest of my capacity.

With the solar and 8Kva multiplus-ii, peak charge current would be 48V 240Amp which would be split over the 6 sets of batteries (40A per cable) with the current draw from the inverter being <180Amp again split over the batteries (30A per cable).


Graham Walmsley asked
Graham Walmsley answered ·

2 Answers

What is the max. current through the Energize terminal of the battery isolator 120-2 AC?

Hello all,

I use the battery isolator 120-2 AC to charge redundant batteries (24V, 150Ah each) with an alternator. To ensure the excitation of the alternator, the isolating diodes have this special Energize connection.

According to the datasheet, the Energize is a current-limiting connection for start-up excitation. What does current limiting mean? How much current can flow max.

And does this current only flow to the input connector into the alternator or can the current from Energize also flow to one of the output connectors?

The line to the Energize connector is fused with a 6A fuse. But it keeps blowing out. Therefore the questions.

As an additional note to Victron, please provide more info in the datasheets.

Thanks and greetings

eduard asked
Alexandra answered ·

2 Answers

DC isolators between PV panels and charge controller.

The victron circuit diagrams always show dual pole PV Breaker/isolators between panels and MPPT, however, various sources online suggest they are not necessary, and potentially detrimental.

My space is severely limited and my panels size quite small and all individually feed their own MPPT.

Are they important?

sweyn asked
kevgermany commented ·

2 Answers

Battery Isolator Challenge

Installed 3 output isolator. Per instructions removed and bypassed the solenoid connection to go directly from Alternator B+ to isolator input. House battery began to discharge rapidly so I disconnected the new connection. One possibility is the alternator B+ wire was crimped with the ignition switch wire. So I think I should separate the B+ and ignition leads. Then reconnect the B+ to isolator input and reconnect ignition wire to solenoid. Agree?

sailwindz asked
Sarah commented ·

0 Answers

Victron Galvanic isolator

Hi there i was wondering on your thoughts for Galvanic Isolator size. my boat is in Europe on a 230v shore supply, now i was just going to match the isolator 32A with the shore-side power also 32A. However i have a Victron Multi-plus 12v/3000/120A and using the power assist this can kick out 50A. So do i go for 63A isolator or is 32A ok?

ct-41 asked
mike-g answered ·

1 Answer

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

Argofet connecting

Hello All,

I have bought a campervan that has a argofet installed. (1 input, 3 outputs)

I have a starter battery and a battery bank of two batteries. These two batteries are parallel connected (12v double capacity).

Do I best connect one Argofet output to one of the batteries in the battery bank or do I connect two argofet outputs each to a battery in the battery bank?

I guess the first option is the right one, but i am niet sure .

Thanks you for your help.



remu asked
remu commented ·

1 Answer

How does the ArgoFET battery isolator work?

If one has an ArgoFET isolator connected to an alternator as its input, and has separate outputs to two battery banks, what determines how much current goes to each battery bank? Is the isolator “smart enough” to send more amps to the battery bank with the lowest state of charge, or not? This is an important consideration when one battery bank is the starter bank (quickly recharged) and the house battery bank which requires longer recharging cycle.

awsmits asked
kevgermany commented ·

2 Answers

Arogfet 24/12 bat isolator wiring question

I have a Victron Argofet battery isolator to charge both my 24v(LI) trolling motor system and 12 v(LI) house/start batt.

I have looked at the manual and am a little confused as to how to wire it properly using the battery switch. The diagram shows the battery switch wired to the energize port which is very small considering my ele. start motor draws a large load to start the battery.

Also, I have solar panels to trickle when motor is not in use. Are they wired to the input along with the alternator input?

leo-young asked
Matthias Lange - DE answered ·

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
brucechen commented ·

1 Answer

Argodiode 180A 3 outputs with no D+ in car


I want to install second battery on a van (Peugeot Traveller), and I have that argodiode with 3 outputs. But I cant find (And I search a lot...) D+ wire or fuse o similar, so I dont use it. Because as diagram indicate, D+ input must be connected on the side of the battery indicator, oposite of the wire that goes from that light, to the alternator. Cant find...

So, I Connect everything else, in normal config.. Alternator wire to input, and car battery+ to output 1 (I don´t connect at this moment second battery). But the car won´t start, as indicate "ECO MODE". It seems ECU signal problem... perhaps because I don´t connect D+ input. Don´t know.. anyway.

But I notice some things... with that 2 wires connected, each one in their position, and engine off, I have 12v (12.4 or similar), on tevery clamp!. Input and output1 (and Output2 and ouput3, that don´t haver wires). I think is because Output1, that goes to main battery has 12v. Is normal 12v also on input?? and on output2 and 3?

But as the car don´t start, well... I also connect on the input clamp, the wire from the main (Car)battery. I know.. that is not correct... But I want to make a bridge looking from the normal car config.

So, in the input clamp, I have wire from the alternator, and wire from main car battery. Together. And the car START ok!. All is working fine on the car. With that config, I ALSO have (like normal config), 12v on every output (engine off), and 14v on every output (engine ON).

I have some doubts.. Is normal, that in normal config, I have 12v on each outputs?? What happens If I connect second battery on output 2, if there are 12v, from main battery? It is not supposed is a Isolator? Is the normal config!, with input to the alternator and main battery to output1.

And with TWO wires (Alternator and main battery), connected to input, I also have 12v (off) and 14v(on).. so.. Can I connect second battery to the output?, leaving output1 empty?

xlman asked

0 Answers

What isolators, fuses, circuit breakers or other products do I need to install my System?


I have recently purchased:

- 2 x 48v Pylontech 3.55kwh Batteries

- Victron Multiplus II 48/5000

- Victron SmartSolar MPPT 150/70

- Victron Cerbo GX

- 6 x LG Neon 2 360w Solar Panels

I am wondering what fuses, isolators, circuit breakers and any other products do I need to fully complete and install my system. Do I need a DC Fuse Disconnector straight after the Batteries? Do I need a Lynx Distributor, if yes, what does it do. It would be awesome if somebody could draw a diagram where each isolator, fuse or circuit breaker goes in my setup. Any help will be much appreciated.

jsheehan asked
jsheehan commented ·

2 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
shawn0900 commented ·

1 Answer

MPPT Isolation question

If I have a 24v battery, a Multi-plus II and a Smart solar MPPT wired together through DC distribution buss bar and the battery were to get disconnected/isolated while everything is running, is it possible that the MPPT would keep any loads (such as the Multi-plus II) live due to the incoming power from the PV panels?

The reason I ask is because I have to fit an isolator switch to my battery cables to comply with local standards and I'm concerned that if that isolator switch is turned off (effectively disconnecting the batteries) that it won't shut the whole system down due to the PV panels keeping things live through the MPPT.

I'm aware that I can isolate the panels too through the DC breakers but that would effectively require 2 actions. I am looking for one switch to shut down all loads. (I'm not worried if the PV panels remain active as long as they cant power anything up while this said switch is off)

Brandon asked
klim8skeptic answered ·

2 Answers

Can i use Argo Battery Isolator for two Lithium battery packs?


I have two lithium battery packs 24V/80Ah (NMC) and two battery chargers.

The maximum continuous load used is 45A.

Can i use 'Argo Diode Battery Combiner BCD 802' for lithium batteries and one load?

Thanks in advance.

baris asked

0 Answers


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