laptop computer charger >>solar charge controller >>battery?

[Bob Hammond]

I have an extra laptop charger that's rated at [email protected] output. That's within the output parameters of a standard 100W solar panel. I think it might be useful as alternative charger for my trailer, by routing the output through the solar charge controller. While it may be somewhat slow in charging the trailer battery, it is small and lightweight and so could be kept in the trailer at all times, for when the sky is cloudy and shore power is available.

Does anybody have comments about this idea?

[Bob Hammond]

A commenter on another site wrote about the possibility of blowing an internal fuse inside the laptop charger, which sounds quite plausible because the solar charge controller's input may appear as a dead short to the laptop charger. I suggested that a load resistor be included.

[John61CT]

Some solar controllers do not take kindly to non-panel inputs.

[Bob Hammond]

Well, I'm considering replacing the solar controller anyway, and it's no significant loss if the laptop charger dies. That said, I checked the input resistance of the solar controller and found this:

The Solar Panel was disconnected for all readings.

Battery OFF: 740 K-ohms

Battery ON: a small DC Voltage appears (85mV), but the resistance reads 8.4 K-ohms

The test instrument was a Fluke 179 multimeter. (a fab yardsale find!)

[Graniterich]

I have tried switching power supplies in the past with no success. Was not a laptop charger but similar design

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[RJ Howell]

Similar dilemma here. 12vdc and need 19+ vdc for the laptop. I've debate a step up transformer. I spoke with a couple apple tech's now and they fear the application.. I hoping to hear about someone who has successfully done this.

[John61CT]

This is really not much of a challenge.

12V to 19V DCDC converters are all over.

There are "universal car charger" kits that let you choose your tip&ring jack plug, get the right polarity

as well as the ones for every laptop designed to plug into the ciggie port.

Tool battery chargers for 12V put out a lot of juice.

[Graniterich]

I did, got a circuit board from ebay, four dollars, adjustable output with voltage readout. Like this https://www.amazon.com/Converter-DROK-R ... B06XG2KPTS

Works great

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[RJ Howell]

I did, got a circuit board from ebay, four dollars, adjustable output with voltage readout. Like this https://www.amazon.com/Converter-DROK-R ... B06XG2KPTS

Works great

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That's just what I've been looking at. How long you been using it? You on a MAC?

P.S. Been getting a kick out of Dancin' Bear. Here's my memorial to Owsley 'Bear' Stanley
.

[featherliteCT1]

I hope the laptop charger works.

[Graniterich]

More apple tax, fine products but you pay for it. That would be a shame to have to use small invertor due to the waste. What type of connection is it? If a DC jack I would question that


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[featherliteCT1]

Interesting topic.

[Graniterich]

That makes sense, not straight power

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[RJ Howell]

I have a MacBook Pro 2017 model laptop. The Apple tech guy told me that I cannot use a generic DC to DC charger to charge my laptop because the OEM Apple charger has a special sensor built into it so that no generic power source will work with my laptop. I was told I need the OEM Apple product to charge the computer.

Nor does Apple have a DC to DC charger for my laptop.

The OEM charger is a 87 Watt USB-C Power Adapter. I was also told not to use a charger with less wattage.

I would love to hear from somebody who has found a way to successfully charge a Mac like mine.

Pretty much what I was told as well.. I'm on a MacBook Air. I was using a inverter and charging like at home. I did buy a cheaper laptop, thinking it could become my travel unit if it worked out.. I can't handle using it... I'm Apple spoiled. I'm currently relying on my iPad mini and my iPhone. I should go back and have another conversation with them about the charger you mention.

[Graniterich]

I did, got a circuit board from ebay, four dollars, adjustable output with voltage readout. Like this https://www.amazon.com/Converter-DROK-R ... B06XG2KPTS

Works great

Sent from my KFKAWI using Tapatalk

That's just what I've been looking at. How long you been using it? You on a MAC?

P.S. Been getting a kick out of Dancin' Bear. Here's my memorial to Owsley 'Bear' Stanley
.

Nice, keep on dancing!

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