Wire Ferrules

Victron products have been using wire ferrules for years, but with the introduction of the MultiPlus-II they became more essential. Many people find them very frustrating.   Products like the temperature sensor and voltage sense wires for the BMV series battery monitors come with ferrules already attached on the wires, just like in the photo below.  If you have used these you will already know how much easier they are to use than bare wires.

BMV products

The BMV series products use a spring loaded terminal block and its a lot easier to push in a ferrule than it is to push in a wire.  The wires tend to bunch up or stick out and will do everything they can to not go in the hole, but the ferrule pops right in.   We didnt have any problem sourcing or crimping our own ferrules for these kind of applications.  The standard short insulated ferrule works perfectly well and there are no special requirements.

The next series of products that you can use ferrules on is for connections that have screw terminals.  This would cover all the MPPT Charge Controllers, many of the chargers, and in fact most of the smaller Victron devices.  For these a wire ferrule makes for a neater application but it not essential.  We also didn't have any problem sourcing ferrules and found that the standard length insulated ferrule works just fine.  
The photo below shows the Lynx BMS.  This terminal block is almost impossible to install successfully without using ferrules because it is so small and only works with 18 awg wires.  With ferrules it is super easy, and we found that standard length insulated ferrules worked just fine.

Terminal block of Lynx BMS

And finally we come to the MultiPlus-II.  This is the one that causes all the problems.  It really requires ferrules and it is quite specific about which ferrules will work and which wont.  Try to do it without the correct gear and you will find it quite frustrating.   The image below shown the AC connection area of the MultiPlus-II  12/3000/120-50 2X120V and it shows the spring loaded terminals.  The springs are super tight so pushing a bare wire in there is not going to work.  You have to use a ferrule and it has to be the right size.


Trying to find the right ferrules for this took us some time and it is only when we met up with Ferrules Direct did we make any useful progress.  Ferrules Direct can supply any kind of ferrules and the tools needed to crimp them.  This is where we found out that ferrules are a European invention and that standard ferrules that are labelled 6 awg are not really 6 awg at all, but are just the nearest European equivalent.  Ferrules Direct sell a full range of "TRUE AWG" ferrules that are to exact US specifications for wire size.  For our test installation we used their part number SF133025 True 6 AWG (25mm Pin) Non Insulated Ferrules   We found we had to use long Ferrules (these are 25 mm) and they had to be uninsulated because the insulated ones wont let you push them in far enough.  These uninsulated ones went is so far there was no exposed conductor sticking out.

Uninsulated true 6 awg ferrules

Because it took us so long to get the right gear for this we managed to accumulate quite a few crimping tools along the way and we found that one design was preferable for these ferrules which are extra long.   In the photo below the ferrule goes in the end of the left hand crimper and because it will only go in so far only the end of the ferrule can be crimped.   Using the crimper on the right the ferrule goes in from one side and sticks out the other side.  It will still only crimp half the ferrule at a time but then you can move it and do a second crimp to do the second half.

Finally we come to removing the connection.  This also has been the source of much frustration. The jaws are super strong and once they have gripped the ferrule they won't let go.  You have to push in on the release tab in just the right way using a small flat head screwdriver.  There is a bit of a trick to this.  Once you figure out the trick the jaws will release easily and the wire will come right out.  I have been told that the best tool for this is the Wera 338 series part 008101  which is a 2.5mm tip with a 45 degree bend.  I have one on order and once it arrives I will try it out and make a video.  

Release tab

Why are they making us do all this?   Victron are quite adamant that they picked the absolute best way to make the connections and are not at all apologetic for this.  They understand that it is an inconvenience to have to source new tools and supplies for these connections but decided that the results justified the means.  It has been as frustrating for me and it has been for many of you but now I feel empowered and these no longer phase me.  I have to agree that they are extraordinarily powerful connectors and it is almost impossible to remove them by pulling the wire.   I hope you agree.



Date 5/15/2024

Peter Kennedy

Date 5/15/2024

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