How to wire up (integrate) and inverter?

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jfm

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Following on from the other inverter thread, but putting in a sseparate post so as not to Fred Drift the other one...

Can someone explain the basics of how to wire an inverter into the rest of a 230v system on a boat?

OK, i understand how a freestnading inverter works. The 12/24v side is connected to the battery and the 230v appliances are just plugged into the inverter. But what if you want to integrate it and connect the inverter's 230v output to the 230v ring mains on your boat so you can use the normal 230v sockets on the boat? Anyone one got any wiring diagrams/schematics showing how it is done? Does it need some fancy switching?

I've bought a boat that was specced sans inverter so I want to fit a big mastervolt jobbie or something, and connect it if possible to one or two of the boat's 230v ring mains (not the galley one that has kettle etc), so I can use the boat's normal 230v sockets. Ok I suppose an alternative is to just install an inverter-only ring main and label it "no hairdriers, no irons" etc but I'd be interested to understnad a fully integrated method if it exists
 
Most decent inverters designed for boat and RV use will have a auto changeover whenever mains input is detected - so no need to rig any fancy switching Mastervolt's instructions should answer your questions.
 
I've got a Victron inverter system.

It conditions the batteries automatically, when the boat is not in use (as long as you are on shore supply), and also provides a supplimental output to your generator if required.

I've got a 4KVA genny, supplimented by the Victron 2.5KW. It will also provide short periods of increased output up to 5KW.

All the instructions were clear and it was all connected up within a day!

The supplier was extremely helpful as well.
 
I sent JFM a PM, but he suggested I posted it here:

I think you want a Masterswitch if you're looking to stay with Mastervolt stuff (I would), or any other similar AC transfer system.

So for example, the mains circuits are split into two groups - high current (AC, hob, washing machine, oven, battery charger etc), and low current (sockets, fridge, TV etc). 3 power sources into the transfer device (shorepower, generator and inverter). High current circuit is only powered when on generator or shore power.

The system automatically switches to whichever is available. Generator is preferred over shorepower with inverter the last option. You do get a short interruption when it changes over but hardly noticable. The TV sometimes resets, but the my Mac Mini doesn't.

Okay, if you plug in a large kettle into the mains when on inverter, the inverter trips but it can cope with most things.

You may need to do some work if retrofitting to split out the high & low current circuits - but its worth the effort for the considerable ease of use afterwards.

Rick
 
[ QUOTE ]

I've bought a boat .....

[/ QUOTE ]

Ooohhhhh eerrrr

Is it still a secret, or are we allowed to ask what it is?? /forums/images/graemlins/smile.gif
 
Double pole relay ( power relay, 60A contacts ) switching the mains between shore and inverter. Coil (220v ) of relay energised by shore power. Plug in shore power, relay energises and switches to shore power driven. No shore power, inverter drives the plug circuits. Cost around £10 for relay and base.



mains-1.jpg
 
[ QUOTE ]
I'd be interested to understnad a fully integrated method if it exists

[/ QUOTE ]It does.
I can't tell you a lot about the technicalities behind it, because I didn't go that deeply in my evaluations, but I've seen a number of US long range boats equipped with such systems. They supplied AC to the whole circuit, with the only exception of A/C and watermaker (yes, including washing machine, dryer and all appliances!). In some cases, they could even handle both 120 and 240 VAC.
Among them, Xantrex is considered one of the best as far as I understood.
Mind, they were rack mounted, together with big electric panels, in full height utility rooms whose size would have been enough for nice guest cabins...
...and I guess they're rather expensive either, judging just by the look of them. Pretty serious equipment.
 
I'd look at the Victron Multiplus range. Fitted one to my SS M38. Was a real easy fit. Just cut the shorepower cable and fed the ingoing shorepower into the charger/inverter and connected the other end which was in effect the mains ring. A small remote switch panel lets me select shorepower as before with the option of limiting the AMP take if a low amp socket. Flick the switch and the invertor comes into play on the mains ring. if you go big enough in size you can it can run hair dryers, cookers. Mine heats water but I did downgrade the heating element rather than buy a larger inverter. I find that 15 mins just heats up enough water in the top of the boiler to fill a washbasin or two.

Rlw
 
Our Waeco unit is auto switching, so the incoming AC is fed into it, then the the output is routed up to the main distribution panel. The only change is that the battery charger is fed direct from shorepower. If you PM me an email address, I can email you the wiring diagram.
 
The victron quattro
http://www.victronenergy.com/inverters-chargers/quattro-12v-24v-48v-5kva/

does exactly what you want,
very easy to install, connect the battery's, the gen output, the shore power, and two output cirquits, one is your standard 230V cirquit, and a second one is all high power loads that don't have to work if the genny nor shore power is available.
Alle necessary drawings and connection diagrams are available in the webside

we use this for professional applications; Outside Broadcast Vehicels
listprice on a 5Kw model (12V or 24V) is 2150 euro
 
Or for a real cheapo version, run a lead from the inverter to the shore power socket - and just switch the plugs over... /forums/images/graemlins/smile.gif
 
Thanks everyone for those really useful replies.

Thinking about it, I want inverter 230v ONLY to the ring main in the saloon, where I can see who is plugging what into it, and I dont want to have inverter power in galley/cabins. I also want a small inverter say 500w. This set up avoids a big load on the batteries from heavy current 230v items, which suits me becuase I dont want to work the batteries that hard and risk flattening them. I appreciate the inverter automatically turns off if the batteries go flat but I dont want to get to that point and I have a perfectly good genset for heavy duty 230v. All I want the inverter for is laptops/mobile phones/TV in quiet anchorages where I wont run the gen set all evening.

So, the circuit in nimbusgb's picture works perfectly for me. Thanks loads nimbusgb. The double pole relay with a 230v coil is (i think) what mastervolt sell as a "Masterswitch", as linked to in Rickp's post, so I'll order one of those. I'll install it behind the boat's switch/breaker panel in the 230v section, easy peasy

Thanks. Job done (nearly). Perfect!
 
Excellent wiring diagram Nimbusgb, I will be modifying my circuitry accordingly. I have one question - Is the inverter ie the fan running all the time the 12 volt supply is on?, or have you another switch or relay in the circuit. I ask this as my inverter is not easily accessable to switch on/off. Thanks Geoff
 
In nimbusgb's diagram the inverter is always connected to the batteries so you'd want to turn it off when leaving the boat etc, to stop the fan, etc. Many inverters have a plug-in remote on/off switch, so you can locate the inverter close to the batteries (so short cables) and have the on/off switch in convenient place. But if you dont have remote switching then I'm afraid you'd need to install it (eg a simple relay) or get to the inverter to turn it off

My boat already has a Mastervolt batt charger so following this thread the kit I have ordered is a Mastervolt Mass Sine inverter 24v 800w. This will match my batt charger so look nice in the engine room. Then I've ordered a mastervolt MICC panel which gives me remote control and monitoring of the charger AND the inverter on one panel, very neat. And finally I've ordered the masterswitch (linked to in rickp's post) to integrate the inverter into the 230v wiring, and I will install that as per nimbusgb's picture so it controls just one ring-main, which is how I want it configured. All that is about £1000, gweep, but very nice machinery. Useful thread, thanks everyone
 
A word of caution about using a plain ol' relay .. you should really use 2 relays with a small delay between one opening, and the other closing .. a single cycle(50/60ms) is enough, as the 2 AC sources won't be synchronized. If shore power is at positive peak, and genny/inverter is at negative, an instant changeover will cause all sorts of problems. Equipment should stay "up" for up to 2 missing cycles.
 
Nice integrated solution.

Thats the sort of thing that done poorly ruins the resale value of a boat, rubbish and ill thought out systems really get my goat!
 
Hmmm, not sure about using two interconnected relays as this introduces a possibly catastrophic failure mode. What if the relay that is supposed to drop out sticks closed and the other one also closes? Unless you have some overly complicated interconnections on the switching side you will have both sources connected together (=instant sunshine /forums/images/graemlins/blush.gif)

IMHO the inherant small delay in a power relay of this size would probably be enough to avoid any problems- given that we're not running powerful rotating plant etc which, I agree, could be a bit fraught. And if it goes wrong and sticks, it just leaves you connected to the wrong (or a non-existant) source. Inconvenient, possibly, but less likely to be dangerous.

Oh, and BTW, one cycle in these parts is 20ms, not 50/60 /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
 
Two relays? Naaaagh, just ensure the two pole relay or contactor purchased has break-before-make contacts, in any case, you will probably only engage the inverter when there is no mains! Keep it simple as suggested! You could use three contacts and have a pretty LED illuminate to tell you your now using the Inverter!
 
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