question

Hi,

Very good book. Full of information!

Thank you.

This is super helpful.

Thank you very much!

I would change the way the links in it work so they open a new page instead of opening the link in the current page. As when you use the back button you go back to the top of the book instead of where you were.

I use Google as a PDF reader. It may be different if adobe is loaded. Being an IT guy, less things installed on a computer the better it works...:) -Bill

Super helpful. Thank you!

Great work, Margaret! Thank you, especially for the numbers and examples! Good to have everything in one doc. Lots of useful information and also tricks that I have not read elsewhere.

If I can wish I would like to have the concrete voltage values for the BatteryBalancer like in the ripple section so we do not have to go to the link for it.

Just a small thing: you can not connect 360W PV array to a 75/15 MPPT charger on 12V as it will be overloaded.

A third proposal: as most of the manuals are missing the right torque values, a torque table would be of much help.

Thanks again.

Viktoria

Stunning stuff, thank you Margreet. And of all the things that caught my fancy, the treatment of the Victron logo on the opening page is a masterstroke of art. (Don't you ever edit that out Matthijs, it's a gem).

I encourage the use of links too, whether they be to Victron kit or even outside suppliers such as cable maufacturers. Doesn't need to be to a product even, just well-written info from anywhere, for those who wish to delve deeper into a topic.

And yeh, "writers are never forgotten". I hope Matthijs remembers at salary review time.. :)

Good work.

Nice book. I am not really the target audience being electronic trained but its nicely done.

Good to see someone sharing my hatred of cigarette outlets (which are a complete bodge never having been designed for power) but I think its really missing an alternative. Personally I am using Lemo connectors for consumer 12v outlets, really nice fittings not really for mass market and I wouldn't recommend them to the general public. I am sure people could do with a good alternative but I am not sure what is best to use?!

Also missing within connectors section the general purpose multi connectors for 12v use to allow removal of appliances etc. To me you should alway be able to pull out the fridge/whatever and disconnect a connector behind to allow it to pull out (like the 2.8mm and 6.3mm spade connector range)

The ratings are actually a little higher than I remember but there are limits to what is sensible in the size in terms of termination (page 57). Suggests you can get 15A through the 1B, not sure I would dare but I suppose 15 failure is 10 operating.

https://www.lemo.com/catalog/ROW/UK_English/unipole_multipole.pdf

By the time you get to the 5B series your into some serious current ratings for the two pole connector (but the connector costs for a 5B are probably prohibitive)

Margreet,

Just got around to reading the book, it's great. Not sure what Victron is paying you, but it's not enough. Sorry Matthijs. :-)

@Margreet Leeftink (Victron Energy Staff)

Second a prior post about including the importance for proper torquing of connections. It's a pet peeve of mine.

Pat

Nice collection of engineering notes. A few comments -

1) Could emphasise danger of wearing jewellery (incl. ring!) or any metallic items when working on bare busbars. Uninsulated spanners are not the only cause of shorts.

2) Some battery isolator switches are not designed to break current (esp DC current).

3) Some words about best practice in shutting down and restarting DC systems may be helpful. E.g. sequencing shutoffs, and precharge before restarting etc. These practices improve contactor lifetimes and minimises the possibility of arcing which may trigger further undesired actions from being startled.

Excellent work on this, with the section on earthing, off grid, grid connected etc.

It would be good to have a note on what the ground relay tick box in ve config should be set to for the different system types.

Hi

A good read

Was interested in the ve bus connection and disconnection. Haven’t read in any of the manuals etc about the implications of disconnecting the negative supply when the ve bus coms cables are still connected to the ve bus and the possibility of damage

Regards

Mike

Hello:

Check the formula on page 5.

Hello:

Check the formula on page 5.

Hello, @Margreet Leeftink (Victron Energy Staff) & all. Please review the "rule of thumb" for AC wire gauge calculation at bottom of the document page 33. That seems to be calculating a gauge too small from the ampacity standpoint.

Margreet's book might do well to explain "nominal current" should be the pass through amps if the inverting amps is smaller. Emphasizing that the rules of thumb are based on copper conductors (instead of aluminium) also might help first time Victron users.

My math below is based on the National Electrical Code commonly used here in the US. Acknowledged that wire gauge practices for a boat or caravan--or a solar home outside the US--may be different & governed by ABYC or other standards.

If pass-thru is 100 amps AC, dividing by 8 = 12.5 mm2 cross section which seems about two wire sizes too small for ampacity. Dividing by 4 seems better which would yield 25 mm2 wire cross section in this example. (For American readers, 25 mm2 is comparable to #4 AWG.) Voltage drop should also be calculated & the biggest wire gauge result trumps the smaller one.

Margreet mentions the Victron toolkit phone app--but the Wiring Unlimited document might do well to emphasize that the phone app only calculates for percentage voltage drop & doesn't calculate for ampacity.

I remember the original Energy Unlimited book from Reinout & company in the early 2000's & Margreet's new book is a worthy successor.

Definitely we need torque values for the AC & DC connections & even for small things like temp sensors or relay terminals. The various installation books need this info, as well,or maybe that should go into the Victron Toolkit @mvader (Victron Energy Staff).

Thanks & Jolliness

I had been searching around for something like this book for quite some time. Finally found it. Thank you....game-changer!!

Hi Margreet,

Thank you for this excellent resource. An essential reference for anyone planning a renewable energy system.

I noticed in Section 3.3 Parallel Battery Wiring, page 19, the diagrams of "correct" parallel wiring, appear not to be the best option.

IOTA Engineering published an article on the subject of balanced charging. https://www.iotaengineering.com/pplib/balancedcharging.pdf

Here is an excerpt;

Also of note, with regard to the installation of an RCD(s) within a system. No mention is made of the NEC Code requirement that an RCD must be installed between a PV array and the MPPT.

This information should be included within 4.10 Solar panels and page 56, Where to mount a RCD.

Also, on page 61, the statement;

This was an excellent read.

Thank you very much.

As a suggestion for completeness on the topic, I would add a section that speaks to why a Precharge Circuit might be needed when using large inverters with low resistance batteries (ie. Lithium).

Something like the info contained in this link

Thanks again for putting this together.

Hello, @Margreet Leeftink (Victron Energy Staff) & all. I'm a Victron distributor in the USA & here are suggestions:

(1) Page 54 of version 05 Wiring Unlimited (discussing AC wiring) underscores the importance of following the product manual for "recommended cable lengths & thicknesses". However, the manuals for Quattro & Multiplus contain no chart for AC cables; something as simple as the chart for DC cables would improve the manuals.

(1a) The phone app Victron Toolkit addresses only voltage drop considerations for wire gauge decisions, but does not address ampacity considerations. Margreet, since the Toolkit app does calculate AC voltage drop for us, is there a target range of recommended AC voltage drop that would help people size their AC cables just right?

(2) Example: I've fitted a Quattro three phase trio with a 100 amp AC input breaker & a manual bypass switch, and the 50 hz Victron system is 230 volts from each phase to neutral, and it's 5 meters (one way) from the AC bypass switch to each Quattro--& the AC cabling would all be equivalent length/same cross section. The Toolkit app says we'll have only .3% voltage drop in that scenario with 25mm2 copper cables (7/10ths of a volt). Does this seem too fat, too skinny, or just right? The cable I'm considering has an insulation rating of 90 degrees C & I need to buy it soon. I'll probably use a second 100 amp breaker on the AC output & the same cable gauge, FYI.

(For community members in the USA, 25mm2 cross section is the same as American Wire Gauge #4.)

(3) Page 56 of the WU book discusses "chassis earth" connections, but has no guidelines on proper gauge for those connections relative to a particular inverter model. The manuals for Quattro & Multiplus are also silent on this topic so this is another opportunity for improved documentation.

(For community members in the USA, "chassis earth" is analogous to how we "bond" all the metal enclosures & frames together as part of the grounding system.) I'm considering #8 AWG copper for the earth connections in the above described Quattro setup--same as 10mm2 cross section--OK?

(4) Could Margreet's book be added to the Victron Dropbox? This way the latest version would always be the one that Dropbox participants would be referencing.

Thanks as always, community folks. Keep the sun shining.