AutoTrail power drain...but what could it be?

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MH04RMV

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Cheyenne 632 SE
Hello Everyone,
I've recently been trying a portable power bank, and thought I'd see if I could run the MoHo off of it for a period of time.

Everything connected OK, but the power bank was showing a drain of ~850w, even though nothing was turned on (as far as I could tell), i.e. Sargent charger was off; tv was off (at the plug); fridge was running on gas; no lights on; no heating (air or water) on; no fans on.
There's no inverter fitted.

Am slightly confused/concerned what could have been draining that much power, with everything "off".

Does anyone have any idea what it might be?

Cheers,
Rich.
 
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Are you plugged into the EHU on your motorhome?
If you are it could be charging you leisure batteries if they are not fully charged.
 
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Are you sure you are reading right 850 Watts is 70 amps, if you are your wiring will be getting very hot.
 
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850w on 12v = 70 amps thats a lot of power going somewhere.

Lenny beat me to it

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I would suggest checking directly you van wiring with a decent meter to see if it has a draw, rather than relying on what the power pack suggests
 
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I don’t know anything about watts of amps but I was told the automatic step always drew power even when the Sargent was shutdown and you had turn off the RCD/MCB to kill it. I had a couple of flat batteries when the van was in storage but since doing the turn off it’s been fine.
 
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I expect the fridge will be using a very small amount of 12v power ,even if being operated on gas , for its control electronics , when it is switched on . (not 850w though ! )
 
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Thanks for all the replies/suggestions.

Radio is "off" (i.e. no display showing though appreciate there will still be something being used).

The power pack was connected to the EHU via standard EHU cable, length ~7m (to replicate a normal EHU connection, and to allow everything/all 3 pin sockets inside to be used as normal).

The Sargent charger was switched off, so I presumed this would not be charging the leisure battery...is it possible it could be then???

I'll have another play with it all and see if I was reading things correctly (will try and take a pic of the output from the provided app), though I presumed that as the power bank was effectively working like a EHU supply, the reading was correct...

Cheers,
Rich.
 
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MH04RMV said:
The power pack was connected to the EHU via standard EHU cable, length ~7m (to replicate a normal EHU connection, and to allow everything/all 3 pin sockets inside to be used as normal).

The Sargent charger was switched off, so I presumed this would not be charging the leisure battery...is it possible it could be then???
Click to expand...
Plugged in like that unless you can switch the mains off to the Sargent unit it will be charging the batteries. If the batteries are a bit low it could be taking 500 Watts or more..
Also if an AES fridge that will switch to mains on auto setting so another 200—300 Watts.
 
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Lenny HB said:
Plugged in like that unless you can switch the mains off to the Sargent unit it will be charging the batteries. If the batteries are a bit low it could be taking 500 Watts or more..
Also if an AES fridge that will switch to mains on auto setting so another 200—300 Watts.
Click to expand...
All the same Lenny.....70 amps through a 16amp hookup cable..
Plus, god only knows how the cable is connected to the power bank.
 
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pappajohn said:
All the same Lenny.....70 amps through a 16amp hookup cable..
Plus, god only knows how the cable is connected to the power bank.
Click to expand...


It will just big plugged into the powerbank with a household 3 pin plug.

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Lenny HB said:
Plugged in like that unless you can switch the mains off to the Sargent unit it will be charging the batteries. If the batteries are a bit low it could be taking 500 Watts or more..
Also if an AES fridge that will switch to mains on auto setting so another 200—300 Watts.
Click to expand...
Hi pappajohn,
The power bank (it's an EcoFlow Delta Max) is able to supply 240v to household appliances (e.g. hairdryers, fridges etc. etc.), so as Jo662 says, it was connected using a 3-pin to EHU connector, and then EHU cable to the MoHo EHU port.
There were no signs/suggestions from the unit that it was being overloaded while it was connected up (it has an auto-overload protection circuit), and I couldn't smell any hot cabling...

Hi Lenny HB,
I thought that if the Sargent main switch wasn't on, it wouldn't be "working" to charge the leisure battery? If it is/could be, then I presume that's a serious fault and would need to have it checked?!

Alas, my fridge isn't an auto-select one, manual all the way...

Cheers,
Rich.
 
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I still think the power draw must of been from the leisure batteries as they were topped up.
 
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MH04RMV said:
Hi @Lenny HB,
I thought that if the Sargent main switch wasn't on, it wouldn't be "working" to charge the leisure battery? If it is/could be, then I presume that's a serious fault and would need to have it checked?!
Click to expand...
Don't know much about Sargent unit but I assume it works like all other Motorhome charger/distribution units and when mains is connected to the van it charges the batteries and the main switch on the unit just turns off the 12v circuits. All perfectly normal.
 
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MH04RMV As Lenny HB has said , the Sargent PSU black shut down button disconnects the 12v habitation electrics but , when on EHU ,the charger can still be used ,even if the shutdown button is in use , via its own on/off switch that is on the PSU switch panel.
 
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GeoffnDee said:
MH04RMV As Lenny HB has said , the Sargent PSU black shut down button disconnects the 12v habitation electrics but , when on EHU ,the charger can still be used ,even if the shutdown button is in use , via its own
Click to expand...

Thanks GeoffnDee Lenny HB - these are the switches on my 2007 Sargent unit.
The red "Charger" switch was off when connected up to the power bank...so are we saying in this instance that "Charger" doesn't actually mean charger for the leisure battery via the EHU, but for the Sargent unit itself to run the 12v items?

If so, am even more confused/concerned, as with this switched off, I can still turn on/use 12v lights, water pump (via the main "control panel" above the habitation door) etc...

Cheers,
Rich.

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If you switch off the RCD on the left, that should cut all mains power. The consumption from the power bank should drop to zero.

Next, with the RCD switched on, switch off the other three MCBs. Again the consumption should drop to zero.

Then switch one of the MCBs on, and check the consumption. switch it off and try another one. Then at least you will know which circuit is drawing power.

Do you have a Truma heating system with electric options? 850W sounds about right for one of the heating elements.
 
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MH04RMV sorry to confuse you , the later Sargent PSU have a dedicated shutdown button that your 2007 PSU does not seem to have. But if you look at the manual for the PSU2007 the charger switch is shown as a Power Switch which could be the same ?. If you do not have it the manual for your PSU2007 can be found on the Sargent Electrical website in the Support section/manuals
 
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My 2 peneth …
I have that Sargent unit. If the charger switch (red one at the top of your photograph) is at off when on ehu the batteries don’t charge but the 240v sockets are live. When the switch is at ”on” then the batteries start to charge also.

Admittedly, I only assume this because of the values changing on the control panel above the hab door when the charger switch is turned on (they go up to a boost / float level) and not because of checking with a multi meter. The values drop if this switch is set to off.

My van is not new to me and so someone may have messed with it but all made sense to me at handover.

here to learn,
Cush
 

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Hi Everyone,
I'm back from my travels now, so will go through the steps suggested by autorouter and Cush, and see what's on and where it's draining.

Will update findings once I have them.

Cheers,
Rich.

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Hi Everyone,
Posted this on a diffferent thread, but it covers the resolution...

!!PROBLEM SOLVED!!

Sooooo...having flipped all of the MCB's and main "Charger" switch off on the Sargent PSU, opening every conceivable cupboard/door/hatch and discovering "hidden" on/off switches and turning each one on/off in sequence, I found out (as Cush mentioned) that there is indeed a separate on/off switch for the water heater (& fridge & oven (for the hot plate)), hidden under one of the seats and under the oven.
With the hidden water heater switch off, no drain on the power bank.
With the hidden water heater switch on, ~850w shows as output/drain on power bank...so...each time I've been connected on EHU at home or on site, I've been heating the water heater...even when I thought I'm using gas to do so (which I guess has ultimately been wasted as not "doing" anything)! Grrr.

Anyhoo, at least now I know where some extra switches are...

Thanks again everyone for your hints/tips/input.

Cheers,
Rich.
 
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