Hi,
I finally had a decent budget to do a DIY build on my catamaran sail boat, converting from AGM house batteries and Scheiber display/controls, and so I chose victron, and below are the various parts of the system.
I am a firm believer in the safety of Lifepo4 batteries (a lot of confusion out there over the different types of Lithium Ion based batteries, Lithium Ion does sound like Lithium Iron!) and I am a firm believer in an integrated system from a single manufacturer where the safety and protection systems are reliable and simple especially for my non techie crew. (I am not saying that this cannot be achieved with other battery brands and BMS etc, but for my insurance company, my non techy crew and a set it and forget it scenario, I believe in this Victron system.
This project involved removing an existing Scheiber CAN bus control system, AGM batteries from Exide, AC/DC chargers from Cristec and integrating a new system in to the original wiring concept of Beneteau / Excess.
I am going to show a number of components that are not just blue victron boxes, but parts that make up the overall system, including distribution and some accessories
1: Human Machine Interface (HMI) and Physical controls
I am not the only person that uses the boat, and not all the others are as technically minded as I am, so controls and operation need to be easy, intuitive and simple.
I removed the Scheiber control screen from its original place in the centre of the boats dashboard at the Nav Station and replaced with with Ekrano GX and a Seaflo Alarm sounder which is connected to the Ekrano relay as an alarm output. This inexpensive sounder has 95dB and an LED and is enough for us to hear alarms as the Victron buzzer is too feeble to get me out of bed or to hear over the wind / seas / engines / party etc…
Old navstation:
New navstation:
Close up of the Ekrano with the Seaflo alarm sounder:
I am looking forward to Venus OS version 3.70 with improved digital switching and shelly support, as there are some great ways to simplify tasks for my crew.
As the Venus has its own power supply from the Lynx BMS AUX I am rely on it to work and give alarms even when the entire system is in standby or other systems have tripped, blown fuses or whatever.
Tank monitoring
The LPG Tank is using a bluetooth Mopeka Pro sensor. Works fine.
The other tanks use wema in tank senders and these used to be connected to the Scheiber, but now that they are connected to the Ekrano, I have seen improved accuracy and resolution.
I have some manual controls too:
Pressing the emergency stop button will turn off the entire system (except the Ekrano). It is a normally closed emergency stop button wired to the REM terminal on the Lynx GX.
This should not normally be done, but if we do need to turn things off in a hurry instead of browsing around for a button in the HMI screen, we can just press this. Digging around under the bunk to get to the system is tricky so this button is in a control cabinet in a companionway.
Also note the 24v Master Switch. My catamaran is sadly a 12v boat and it was too complicated to step up to 24/48 for this project, but I did need some 24v for the IT systems. That button is wired to an Orion TR DC/DC converter REM terminal and simply turns off all the IT (computer, network, wifi, starlink) kit. A quick and simple way to reduce loads if needed.
The old Scheiber control panel is still there as my budget did not extend to an AC/DC charger for the engine batteries, so there is still a Cristec and this managing that part. One day….
There is also the obligatory SHIP / SHORE changeover switch for the inverter.
Android App
We have a mobile HMI with the new Android app on a cheap Oppo phone. This has proven to be very reliable. It normally lives by my bunk in my cabin next to a raspberry pi with Wind and Nav info.
2: Batteries
Old Exide AGM with the weird and prone to failure Scheiber monitoring on the neg terminal.
These batteries were 140AH each, giving a usable capacity of about 300 Ah.
The new bank is 4 x Victron Lithium NG 300Ah each giving a total usable capacity of around 900Ah.
The new batteries are exactly the same size as the old ones. Total weight of the new bank is 140Kg less than the old bank. This matters on a catamaran.
Following photos show the thought process of laying things out.
Option 1:
Option 2: I went with this option as easier to maintain equal length battery cables.
Given that the Lifepo4 cells are in the blue casing there is no need for a separate battery box. I love the new hold down brackets on the new NG:
Worked hard to keep the battery cables all same length when wiring to the Lynx Power In. One of the hardest things to find for this project were the Class T fuses. I was getting crazy prices too.
Finished battery box with Lynx Distribution and BMS
3: Charging:
3.1: AC / DC
I replaced Cristec AC/DC chargers with the Skylla IP65. I have mixed feelings about this machine and wish that Victron had an AC/DC charger that would work with DVCC. Anyway, I have the REM terminal of the charger connected to the ATC terminal of the BMS so that the BMS can stop the charger if it wants (mainly when the BMS is turned off from HMI or Emergency stop).
Old Charger:
New charger with ve.can:
3.2: Engine Alternator charging
I have 1 Orion XS at each engine (2 engines). The yanmar alternators are rated at 120A and given that we will never get that out of them, I just have a single Orion XS to each engine and these are programmed to charge at 45Amps in the hope that we dont stress the alternators too much.
Orion XS and fuse.
You will see existing Cristec Diode there which I didnt have budget to replace.
3.3: Solar Charging
The boat came with solar already installed:
4 Strings of 100w connected via USB hub and USB to ve.direct cables
1 string of 960w connected by ve.can
The aft panels are Bi-facial and I really like them.
4 Distribution
I used qelectrotech free electrical cad software to sketch out a plan.
1.pdf (9.6 MB)
Galvanic Isolator
The boat didnt have one. Perhaps less of an issue in Europe… We dont spend much time connected to shore power, but it seemed easy to do for the cost and peace of mind. Some recent horror stories abound too.
AC Distribution and stuff.
The cost of actually installing is quite significant. Cabling for a Lifepo4 battery which can do 300Amps at C1 rate needs to be substantial.
Cable lugs, cable management, breakers, RCBO, labelling and on and on, all adds up quite quikly.
Not to mention the tooling. A decent 7ton hydraulic crimper for example.
The control cabling, in the form of ve.direct cables (I hate these), belden signal cable, USB hubs and extensions adds up too.
Here is the Victron Shore power meter with USB interface cable.
The main distribution panel has Inverter side and Non inverter side. Non inverter side has the supply to inverter, supply to AC/DC chargers, supply to hot water tank.
5: Loads
The boat came with a new but uninstalled 3kva inverter which we squeezed in to the designated spot. There was no inverter previously.
DC/DC Orion TR Converter
I used this to bump up from 12v to power starlink and the network.
The Skylla AC/DC Charger came with a temperature sensor that is not needed with lifepo4 so I used it to monitor the temp of the Orion
6: VRM and Alarms
Of course everything goes back to VRM. I havent really spent time with VRM yet as have been busy sailing. The boat will stay in the water for winter and so I spent some time to add some additional high water bilge alarms that will notify me by phone and email.
Here I am using a Johnson pump SPXFlow float switch, connected with Wago connectors inside a Wago IPX8 waterproof enclosure. They are wired directly to the Digital inputs of the Ekrano. No other power supply needed.
7: How the system has changed our lives
We have had the system since March this year and as we end this sailing season, here is how it went.
Following picture says it all. Its a washing machine on a boat!
Its been brilliant. Perfectly reliable.
I couldnt get cooking gas in Montenegro, so went and bought a table top induction hob, and that saved us for about 3 weeks.
My wife is keen on all the comforts, and we have starlink (quite the hog, even though converted to run on 24volts) computers, Apple TV toaster, microwave etc (i know there are some purists out there who think this is mad, but I get to own and enjoy sailing only if my wife is happy and comfortable. So that is the key thing that this system has enabled for me personally, is to keep everyone happy and safe.
I came across this youtube video about using an regular household AC fridge versus a so called Marine grade DC compressor fridge.
DON’T Buy an Isotherm / Indel B 12V FRIDGE Until You Watch This
I have been a user of Engel chest fridge / freezers for decades on safari in Kenya so I assumed that marine fridges would perform similarly. The isotherm compressor frodges this boat had are absolute trash. Climate class is all wrong. The thing runs the compressor full time until it times out and can only achieve 12.8 degrees c firdge temp in 32 degrees summer heat. Crap.
Watch the video and tell me what you think? Either way I am going to do it and seeif things improve next year. In fact I bet that this victron system will power that Climate Class T fridge for less cost and less energy.
Here is a use case for the android app. Filling water to our tanks requires sitting there holding the hose (until I can get a 3d printed adapter), so we bring the android phone out with a cup of tea and hold the hose in. This takes about 40 minutes.
