Where to connect a 1000W inverter

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milnei

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Hi all.

I've connected my 1000W inverter to my CLS 320CDi under the parcel shelf in the trunk, and run a 2 socket extension lead plus remote inverter on/off switch to the rear centre console between the rear seats.

The +12v supply is designed to be connected directly to the battery which I've done and it's a great installation and I'm pleased with it. It keeps the kids laptops, ipads and/or DVD players charged on long trips and means I can power the odd 240v appliance when necessary directly from the car.

I know 1000W is a bit of an overkill but I'd got fed up with the usual 300W inverters failing to deliver or overheating at times of need.....

However I was plodding through WIS and noticed that the car has two batteries, the main one in the trunk and the aux in the engine bay. I then read in WIS document GF-54.10-P-0001TX that 'It is not permitted to connect electrical devices (consumers or charger) directly to the battery terminals of the battery by bypassing the current sensor..

Does this mean I've been a naughty boy and I'm risking damaging or confusing the car, or is it actually 'OK' to connect the inverter directly to the battery as I've done?

If I shouldn't connect directly to the battery, where should I get my permanent +12v feed from?
 

television

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If it all works OK leave it, you will find it too hard to find point capable of supplying the 83 amp under full load
 
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milnei

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True about leaving be, but wondering if there is an authorised pickup point for 12v loads.
 

mersum1es

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I was also reading WIS yesterday, and found same statement (W211)... if I remember right there was some note that it's related to the proper function of the battery charger control unit.
 

whitenemesis

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True about leaving be, but wondering if there is an authorised pickup point for 12v loads.

From MB tech doc.

Adding additional electric accessories:
When adding accessories always use a power supply that is fused through the
pre-fuse boxes. This will ensure that the BCM can monitor the current
consumption accurately.
DO NOT CONNECT ACCESSORIES DIRECTLY TO BATTERY TERMINALS
 

television

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From MB tech doc.

Adding additional electric accessories:
When adding accessories always use a power supply that is fused through the
pre-fuse boxes. This will ensure that the BCM can monitor the current
consumption accurately.
DO NOT CONNECT ACCESSORIES DIRECTLY TO BATTERY TERMINALS

The problem is there is not a spare one that I can see that can carry that load, it is massive when loaded
 

Miffy

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From MB tech doc.

Adding additional electric accessories:
When adding accessories always use a power supply that is fused through the
pre-fuse boxes. This will ensure that the BCM can monitor the current
consumption accurately.
DO NOT CONNECT ACCESSORIES DIRECTLY TO BATTERY TERMINALS

I am guessing here that MB did not envisage anyone wanting to connect something that would draw that amount of current. Saying that, is not the Starter directly wired?
 

whitenemesis

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I am guessing here that MB did not envisage anyone wanting to connect something that would draw that amount of current. Saying that, is not the Starter directly wired?

No, the starter is connected through the front pre-fuse boxe
 

television

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I am guessing here that MB did not envisage anyone wanting to connect something that would draw that amount of current. Saying that, is not the Starter directly wired?

I do not know off hand if the front battery is for SBC or starter on the 219, but either way its still wrong as that battery is charged from the same battery convertor that runs the rear one.

The idle no load current is low, but higher in proportion to the equipment thats running on it, there are losses with inverters.

The OP could add up the total wattage from what will be used at any one time and take it from there.

I also go along that a large 1000 watt inverter has a much cleaner output than the small ones. we went the same way when doing outside broadcast in Sweden in the trucks
 

television

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Just for the record and anyone reading this, computer back up power supplies make perfect inverters, just take out the inbuilt batteries and wire to the car and you have a good 240 volt supply with a good waveform

You can pick them up for £5 with duff batteries, but you do not want them anyway
 

whitenemesis

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I do not know off hand if the front battery is for SBC or starter on the 219, but either way its still wrong as that battery is charged from the same battery convertor that runs the rear one.

The idle no load current is low, but higher in proportion to the equipment thats running on it, there are losses with inverters.

The OP could add up the total wattage from what will be used at any one time and take it from there.

I also go along that a large 1000 watt inverter has a much cleaner output than the small ones. we went the same way when doing outside broadcast in Sweden in the trucks

The front (axillary) battery is only used if the main (rear) battery is low on charge. All consumers are normally supplied by the rear battery.
 
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television

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The front (axillary) battery is only used if the main (rear) battery is low on charge. All consumers are normally supplied by the rear battery.

I know that, but both batteries are monitored not just the rear one
 

whitenemesis

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There appear to be 1 or 2 spares in each of the pre-fuse boxes, according to my fuse assignment on the CLS
 

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There appear to be 1 or 2 spares in each of the pre-fuse boxes, according to my fuse assignment on the CLS

But again are the live feeds to the bus bar large enough
 

whitenemesis

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I know that, but both batteries are monitored not just the rear one

My post was in response to your statement that you didn't know if the front battery was for SBC or starter. It's for neither.
And no one questioned which battery was monitored!
 

television

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My post was in response to your statement that you didn't know if the front battery was for SBC or starter. It's for neither.
And no one questioned which battery was monitored!

It still cannot be used as it is still monitored, that is what I said.
 

television

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There are two consumers rated at 200amp and two at 150amp ..

Perhaps it is worth looking on the rear box as that is where the equipment is, I cannot do this till later, perhaps use a tow bar wiring socket connection that supplies the constant supply
 

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