- Thread starter winchman
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ajlelectronics
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If the Mac battery is over 12V then there is no way other than an inverter. If it is a 12V input, then just a cable should do.
Kram
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A dc-dc boost converter will be far more efficient than a 240v mains inverter. You would buy one to match the required output voltage and current.
ajlelectronics
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It is still an 'inverter' regardless of the input voltage.
Years ago I bought something branded "Juice" - cigarette lighter adapter straight into their box of tricks & then out to the laptop with one of the brand specific adapters. I've made I sound a lot more complicated that it really was & worked a treat.
Something like this does 100W USB-C, so it must deliver 20V from a 12V cigar lighter socket, or accesory socket or whatever the PC version is called these days:
sako243
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No an inverter's output (in this context) is AC.
DC-DC boost circuits (simply) uses a switched inductor and diode to charge up a capacitor to higher than the input voltage. There is not any alternating current flowing in the circuit - current flows through different paths but it's still just DC.
Kram
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I disagree but with regards to efficiency from a battery source, mains equipment is usually terrible, which for me would rule out a 240v inverter.
Dc boost converters can be 95% efficiency with very low losses at idle.
Screwdriver
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10000/20000mah High-capacity Portable Power Bank, 5v2.1a Portable Usb Charger, Compatible With Android/iphone Devices (2 , Type-c, Micro), With Led Display, Safe And Polymer Lithium Battery. - Cell Phones & Accessories - Temu United
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Misterg
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Bite the bullet and fit something like this:
Very low standby power (zero when switched off), pure sine wave and plays well with all sorts of mains adapters.
90% odd efficient.
Chalk and Cheese vs the Chinese inverters on Amazon/Ebay/etc.
Have had one in our camper for the last couple of years and it just works.
Victron Energy Phoenix Pure Sine Wave Inverter - 12V 375VA (VE.Direct-enabled)
Victron Energy 12V 375VA professional, high efficiency, pure sine wave inverter with VE.Direct interface. For caravans, motorhomes, campervans, boats.
www.12voltplanet.co.uk
Very low standby power (zero when switched off), pure sine wave and plays well with all sorts of mains adapters.
90% odd efficient.
Chalk and Cheese vs the Chinese inverters on Amazon/Ebay/etc.
Have had one in our camper for the last couple of years and it just works.
winchman
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Problem is I only have 100ah of battery power so not really enough to run itBite the bullet and fit something like this:
Victron Energy Phoenix Pure Sine Wave Inverter - 12V 375VA (VE.Direct-enabled)
Victron Energy 12V 375VA professional, high efficiency, pure sine wave inverter with VE.Direct interface. For caravans, motorhomes, campervans, boats.www.12voltplanet.co.uk
Very low standby power (zero when switched off), pure sine wave and plays well with all sorts of mains adapters.
90% odd efficient.
Chalk and Cheese vs the Chinese inverters on Amazon/Ebay/etc.
Have had one in our camper for the last couple of years and it just works.
ajlelectronics
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It will only pull the current it needs to drive the devices you have connected.
Misterg
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That's the same problem whether you use the inverter or some sort of 12V supply direct - most of of the power used from the battery will be what the laptop needs, however it gets there.
You've got about 600 watt-hours useful capacity in the battery (to 50% discharge) - if the laptop takes 100W, that's about 6 hours use.
That inverter has got a soft switch on it, so you can leave it wired in and only switch it on when you need it.
A 20,000mAh (or 20Ah) power bank takes something approaching 100Wh from a 5V USB supply to charge it. Factoring in the inefficiency of the charger, that's probably about 110Wh drawn from the supply be it from 12V or mains. That's a pretty large chunk of a car battery's available charge.
The MacBook Pro battery is quoted as 58.2Wh, so around 65-70Wh drawn from the external supply.
The MacBook Pro battery is quoted as 58.2Wh, so around 65-70Wh drawn from the external supply.
Screwdriver
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Yes I would treat it as a consumable in between the availability of mains for topping it up. Depends how long they are planning to "pop out in the camper" and whether or not they are going there to sit in front of a laptop.
Those power banks are so cheap you could take a couple of fully charged items and save all the hassle/expense of a remote DC power solution.
