Adding an inverter - wiring?

[Irish Rover]

My boat has a generator but no inverter. There are 220v sockets throughout the boat which can be powered from the shore power or the generator. I'm going to upgrade the solar soon by adding 2 x 580W solar panels and I have a 3Kw inverter to install, which I took from my previous boat. Am I correct in assuming we will be able to connect the inverter to the existing 220V network without the need for too much additional wiring?

 

[PaulRainbow]

My boat has a generator but no inverter. There are 220v sockets throughout the boat which can be powered from the shore power or the generator. I'm going to upgrade the solar soon by adding 2 x 580W solar panels and I have a 3Kw inverter to install, which I took from my previous boat. Am I correct in assuming we will be able to connect the inverter to the existing 220V network without the need for too much additional wiring?

Make and model of inverter ?

 

[rogerthebodger]

I have a setup for shore power. generator and inverter.

I have a 4 way switch to switch either supply into my mains distribution setup. and an off position

Just change your 2 way switch with a 3 way switch the connect the output from the inverter to the extra position to feed the mains system

I do also have a switch to switch the DC input to the inverter as my inverter has an constant and drain using a high current contactor with a DC coil

 

[Irish Rover]

Make and model of inverter ?

Victron Phienix 12/3000

 

[PaulRainbow]

Victron Phienix 12/3000

Reason i asked was in case it was an inverter/charger, which is wired very differently to a "plain" inverter.

Roger is correct, change to current change over switch for a 4 position* switch.

* It's a 4 position switch that you need, not a 4 way switch. "way" refers to the number of switch contacts. You need a 4 position, 2 way switch.

 

[Irish Rover]

Reason i asked was in case it was an inverter/charger, which is wired very differently to a "plain" inverter.

Roger is correct, change to current change over switch for a 4 position* switch.

* It's a 4 position switch that you need, not a 4 way switch. "way" refers to the number of switch contacts. You need a 4 position, 2 way switch.

Thanks. Much appreciated, as always.

 

[Irish Rover]

I have a setup for shore power. generator and inverter.

I have a 4 way switch to switch either supply into my mains distribution setup. and an off position

Just change your 2 way switch with a 3 way switch the connect the output from the inverter to the extra position to feed the mains system

I do also have a switch to switch the DC input to the inverter as my inverter has an constant and drain using a high current contactor with a DC coil

Thank you.

 

[wonkywinch]

A question, in this situation, is it better to use electronic switching (ie zero volt changeover) when switching between potentially live supplies with loads still connected?

 

[vas]

or sell the Phoenix and your battery charger (especially if its an odd non intelligent one) and buy a Multi (inverter charger) then you can avoid updating the how many ways switch

 

[PaulRainbow]

A question, in this situation, is it better to use electronic switching (ie zero volt changeover) when switching between potentially live supplies with loads still connected?

Manual switching works fine, even with loads connected. I can manually switch sources without interruption.

 

[rogerthebodger]

My 4 position 2 pole switch is break before make so you don't get the possibility of out of phase connected together

 

[PaulRainbow]

or sell the Phoenix and your battery charger (especially if its an odd non intelligent one) and buy a Multi (inverter charger) then you can avoid updating the how many ways switch

Whilst the multi is a good choice, it doesn't make the wiring any easier, IMO.

Why :

You still need the existing switch to determine whether the inverter input is shore power or generator, so you have to run an AC cable from the switch to the inverter, then another AC cable to the distribution board. Being picky, that's an extra cable

The Multiplus AC pass through does not work if it loses power or develops a fault. So you need a bypass switch to enable AC power to pass around the Multiplus. That's an extra switch and more wiring.

 

[Irish Rover]

or sell the Phoenix and your battery charger (especially if its an odd non intelligent one) and buy a Multi (inverter charger) then you can avoid updating the how many ways switch

The charger is a Quick SBC 700. A Victron Multiplus 11 12/3000 is almost €2,000 here. After I upgrade the solar I don't envisage using shore power very often. Is it worth the extra rather than change the switching?

Edit. Posted before I say Paul's post.

 

[wonkywinch]

My 4 position 2 pole switch is break before make so you don't get the possibility of out of phase connected together

My thought was to switch at zero volts to prevent arcing, interference, spikes through electronics etc rather than the risk of connecting two OOP lives together.

 

[vas]

Whilst the multi is a good choice, it doesn't make the wiring any easier, IMO.

Why :

You still need the existing switch to determine whether the inverter input is shore power or generator, so you have to run an AC cable from the switch to the inverter, then another AC cable to the distribution board. Being picky, that's an extra cable

The Multiplus AC pass through does not work if it loses power or develops a fault. So you need a bypass switch to enable AC power to pass around the Multiplus. That's an extra switch and more wiring.

you are of course right!
I'd forgotten that I'm using a voltage sensitive (or whatever they are called) relay thingie that switches input from shore to generator automagically...
Not to mention that I've used shore power once over the last 5 or 6yrs since installing solar. Don't even bother in the boatyard nowadays!

 

[rogerthebodger]

My thought was to switch at zero volts to prevent arcing, interference, spikes through electronics etc rather than the risk of connecting two OOP lives together.

Arcing normally take place when current is flowing not at zero voltage except when current is flowing.

I never change mains supply source with current flowing so no arcing.

If you wish to switch a zero voltage i.e. at sign wave zero point you would need an electronic switching device to detect the zero-crossover point as we used in thirster-controlled DC motors drives, we used on steel tube draw benches we made where I worked in the UK

Arcing is mainly an issue when switching DC currents not AC which at low currents is self-extinguishing arc

In my setup the AC wiring is separate from the DC wiring so very little possibility of induced currents which is how wiring should be done IMHO

 

[KompetentKrew]

The Multiplus AC pass through does not work if it loses power or develops a fault. So you need a bypass switch to enable AC power to pass around the Multiplus. That's an extra switch and more wiring.

You mean if the Multiplus is disconnected from the batteries, it will no longer supply shore power? I wouldn't think that's a big deal to worry about, is it?

I'm not convinced an inverter-charger is always the best answer - I bought the Multiplus because it was replacing a previous, 25-year-old, Victron combi so it just dropped into place and I could keep all the existing wiring as it was. But the built-in transfer switch works well for me, and particularly the PowerAssist feature.

 

[PaulRainbow]

You mean if the Multiplus is disconnected from the batteries, it will no longer supply shore power? I wouldn't think that's a big deal to worry about, is it?

Disconnected from the batteries, the Multiplus fails, or you turn it off = no mains. Plus, there can be scenarios when you want to turn it off and it's not convenient or practical to mess around with settings, so a bypass switch is handy.

I'm not convinced an inverter-charger is always the best answer - I bought the Multiplus because it was replacing a previous, 25-year-old, Victron combi so it just dropped into place and I could keep all the existing wiring as it was. But the built-in transfer switch works well for me, and particularly the PowerAssist feature.

 

[Trident]

I built a solar, lithium , inverter set up on my boat with no expense spared and have lived off it full time for 5 years running everything (cooking, hot water, etc ) and I deliberately chose NOT to run the Multiplus or Quattro but the Phoenix instead with a separate charger. I like to control things myself so have a manual changeover switch but I rarely use it even in mid winter. The way my charger is wired bypasses the switch meaning that I can stay on inverter and solar and just top up with a battery charger if needed . (There is no possibility of the two sources crossing over and interfering )

Long term studies show that even with the "losses" in the charger its still more economic to provide a "battery charger assist" to what solar I do get in the winter than turn on shore power and use that until batteries charge higher again. I'm also just very old fashioned and don't trust technology too much - I can get an electronic 250A changeover switch that works in 11 milliseconds but I can switch manually without interrupting the TV (PCs are laptops anyway) so why add in one more thing to go wrong?

The multiplus is great for many situations, I'm fitting another for a customer this week so his wife can use their Nespresso at anchor (literally the only reason they want it) , chosen because he doesn't want separate sockets or to have to remember to switch over anything so its easy and idiot proof but on a boat where he is never away for more than a weekend and never more than 30 miles from home.

For liveaboards and long term cruising KISS is always the best policy

 

[vas]

For liveaboards and long term cruising KISS is always the best policy

hard pressed to agree with that tbh.
Guess, each to their own, 4yrs using the multi, fancy electronics, canbus bms, all linked via a raspberry pi and an ESP32 with the N2K bus, they all still work and I can check from wherever I am not only what's working and what's not or the soc of the lifepo4 bank, but also how strong was the wind this morning after I left the city and there were gale force winds expected (didn't materialise up to 20kn...)