Inverter (1 Viewer)

[Spartacus]

Hello.

I have just picked up a 2018 Dethleffs Trend Motorhome which is built on a Fiat Ducato 2.3l Diesel base vehicle.

I have found the leisure battery, and believe the vehicle battery is under the floor by the passenger seat. Can anyone confirm this?

There also appears to be some form of electrical connection under the passenger seat. It has German wiring on it so I am assuming this is on the leisure side?

I want to fit an inverter. Ideally I would have it switched on the ignition but for now I don't mind going straight off the battery terminals. Where am I best to wire this into? The battery under the floor or that thing under the passenger seat, or somewhere else to access the +ve feed of the van battery?

Thanks

 

[Rob Turner]

You need to wire it directly to your leisure batteries, suitably fused and as close as you can.
Don‘t wire it to your vehicle battery which is under the floor by the dashboard.
The leisure battery/batteries will probably be under the r/h seat. Maybe the inverter would go under the seat directly behind the cab seat.

You will have to do your maths as to what size inverter you want/need and also battery capacity plus solar.

 

[Spartacus]

You need to wire it directly to your leisure batteries, suitably fused and as close as you can.
Don‘t wire it to your vehicle battery which is under the floor by the dashboard.
The leisure battery/batteries will probably be under the r/h seat. Maybe the inverter would go under the seat directly behind the cab seat.

You will have to do your maths as to what size inverter you want/need and also battery capacity plus solar.

Why the leisure battery?
Why not the vehicle battery?

I do not have solar. I have a 4kw inverter and thick cable. Max draw is 250w as I charge 2 laptops, a mobile phone, and various small devices like headphones, torches, etc.

Wiring to the vehicle battery and running the inverter when the vehicle is running gives me the alternator power. I'm assuming, split charging gives less power to the leisure battery?

^{_{Subscribers  do not see these advertisements}}

 

[funflair]

Usually the leisure battery as it's difficult to start the vehicle with a flat battery it's not good to be running the engine every time you want the inverter on but with a single battery and big inverter it would really be your only option.

 

[Spartacus]

Usually the leisure battery as it's difficult to start the vehicle with a flat battery it's not good to be running the engine every time you want the inverter on but with a single battery and big inverter it would really be your only option.

Why is it 'not good' to run the engine when I want to use the inverter? I generally do it whenever I'm driving anyway. Only if I'm stationary for a few days do I need to idle while my devices charge.

 

[David and Sally]

Idling can clog up the dpi filter. The engine needs to get to full temperature as quickly as possible.

You are much better off wiring to the leisure battery. The box under the passenger seat is probably the ebl for the leisure system.

^{_{Subscribers  do not see these advertisements}}

 

[chaser]

The first thing you need is as much solar power as you can fit on.

 

[Lenny HB]

I do not have solar. I have a 4kw inverter and thick cable. Max draw is 250w as I charge 2 laptops, a mobile phone, and various small devices like headphones, torches, etc.

You don't need an inverter to do any of that, far more efficient to use 12v chargers.
Also if only taking a max of 250 Watts you only need a 300 watt inverter, the bigger the inverter the higher the standby current.

 

[Spartacus]

The first thing you need is as much solar power as you can fit on.

Different conversation. Not an option to get done TODAY

^{_{Subscribers  do not see these advertisements}}

 

[Spartacus]

You don't need an inverter to do any of that, far more efficient to use 12v chargers.
Also if only taking a max of 250 Watts you only need a 300 watt inverter, the bigger the inverter the higher the standby current.

Different conversation. I know what size I have, what draw I have, and what is ideal. Working with what I have is all I can do Today. 12v chargers don't do great for macbook pro charging either. And I only have 1 12v port... Which would require me to run the engine

 

[Spartacus]

Idling can clog up the dpi filter. The engine needs to get to full temperature as quickly as possible.

You are much better off wiring to the leisure battery. The box under the passenger seat is probably the ebl for the leisure system.

 

[Rob Turner]

Best advice I could give you is crack on.

Wire the 4kW inverter into your vehicle battery and let us all know how you get on after your first trip away.

^{_{Subscribers  do not see these advertisements}}

 

[chaser]

Different conversation. I know what size I have, what draw I have, and what is ideal. Working with what I have is all I can do Today. 12v chargers don't do great for macbook pro charging either. And I only have 1 12v port... Which would require me to run the engine

Don't really understand why you are asking when you already know what you are going to do.

 

[autorouter]

Best advice I could give you is crack on.

Wire the 4kW inverter into your vehicle battery and let us all know how you get on after your first trip away.

He's havin' a laff, I think.

When you first try to run a mains appliance off a 12V battery system, it's difficult to realise that the power from a single 13A mains socket (240 x 13 = 3120W) is a huge power load in a 12V vehicle.

A typical car battery is 100 amp-hours (Ah) capacity, and that contains 12 x100 = 1200 watt-hours of energy. In theory it would power a 3120W load for 1200/3120 = .38 hours, ie 23 minutes, before it was totally completely flat. In practice it would probably half of that, or less.

The engine alternator can probably supply about 100 amps, so in power terms that's 12 x 100 = 1200 watts, so you can see it's not capable of providing 3120 watts.

If you look carefully at your 4kW inverter I think you'll find it's a '4kW peak power, 2kW continuous power' inverter, so on here we would call it a 2kW inverter. That's still huge, but not absolutely massive.

So can you connect it to a battery and draw 250 watts out of it? Answer, yes, if you are careful. 250W requires 250/12 = 21 amps from the battery, which is a reasonable load. The alternator can provide 21A, ie 250W continuously with no problem, so it will be refilling the battery as fast as the inverter is draining it.

Which battery to connect it to? The big problem with this kind of thing is accidentally leaving things on, and completely discharging the battery. We've all been there before on this, so we've learnt the hard way that a separate battery for all these devices is the way forward. The leisure battery is still charged from the alternator when the engine is running, but is disconnected when the engine stops and the alternator is no longer charging.

If you had suggested a 300W inverter connected to the leisure battery, most would have said fine. It's just that to me a '4kW' inverter connected to the starter battery is asking for trouble, unnecessarily.

Big inverters have the disadvantage of quite a high 'no-load drain'. They are inefficient and waste precious battery power. It's not so bad if you use power in short bursts, like for a microwave or electric drill, but if for example charging a laptop over several hours, the wasted power adds up.

 

[Rob Turner]

Exactly how I would have put it but I couldn’t be bothered

^{_{Subscribers  do not see these advertisements}}

 

[two]

Hello.

I have just picked up a 2018 Dethleffs Trend Motorhome which is built on a Fiat Ducato 2.3l Diesel base vehicle.

I have found the leisure battery, and believe the vehicle battery is under the floor by the passenger seat. Can anyone confirm this? Yes - the vehicle battery is under the floor on LHS.

There also appears to be some form of electrical connection under the passenger seat. It has German wiring on it so I am assuming this is on the leisure side? Probably.

I want to fit an inverter. Ideally I would have it switched on the ignition but for now I don't mind going straight off the battery terminals. Where am I best to wire this into? The battery under the floor or that thing under the passenger seat, or somewhere else to access the +ve feed of the van battery?

Thanks

Welcome.
You have much to learn and that's going to take time.
My advice is to take things more slowly, one step at a time.
Forget any high power inverter and don't use the starter battery to power one because you'll be stuffed when you flatten it.
Learn to walk before trying to run. Some mistakes can be expensive.

 

[Rob Turner]

A reply off the op would be polite.

 

[tonka]

A reply off the op would be polite.

Can't...
Now a "free member" used up the 5 free posts...
Unless they want to pay up

^{_{Subscribers  do not see these advertisements}}

 

[mitzimad]

Can't...
Now a "free member" used up the 5 free posts...
Unless they want to pay up

cant see that happening as he all ready knows what to do

 

[Just smiffy]

Won’t be teaching him how to suck eggs…..

 

[Tombola]

Im spartacus and so is my wife

You can probably find a +ve behind the drivers seat in the floor holder. But maybe thats a different convo

^{_{Subscribers  do not see these advertisements}}

 

[rnb100]

I'm no electrician, but if you buy a PowerOak or suchlike. They have 2 x 300 watt sockets, 4 x USB points and 12v. I've got one and it does me fine for charging the MacBook Pro, DJI drone, mobile phones, smart watch and 12v TV, so I'm not sucking the life out the leisure battery when not on EHU. It was around £500 and you'll get it within a day or two. Seems like a quick fix to your issue.

I'm going to be chucking 300 watt + of solar on the roof in the next couple of months with a lithium battery, I'll still be taking a fully charged PowerOak with me for back up power until I suss out my requirements, but I doubt I'll need it. Better safe than sorry though.