FS stop Mavic 2 car charger only works while engine is running?

[SteveCA]

I just received my new MP 2 car charger from Amazon. I have have a diesel GMC with dual batteries. The charger does not work unless the engine is running, even though the batteries are fully charged and more than capable of supplying the power to charge the Mavic 2 battery.

Does this thing have a low voltage cutoff!

 

[fstop.labs]

I just received my new MP 2 car charger from Amazon. I have have a diesel GMC with dual batteries. The charger does not work unless the engine is running, even though the batteries are fully charged and more than capable of supplying the power to charge the Mavic 2 battery.

Does this thing have a low voltage cutoff!

When the engine is not running, the car is not supplying power to the 12V line - if you turn your turn to the slot when your headlights turn on/before the start, it should work. It depends on your car though, almost all cars will not have power if the engine is shut off.

 

[SteveCA]

When the engine is not running, the car is not supplying power to the 12V line - if you turn your turn to the slot when your headlights turn on/before the start, it should work. It depends on your car though, almost all cars will not have power if the engine is shut off.

My truck supplies power all the time, unlike many other vehicles. My Mavic Pro car charger charges fine without the engine running but this MP 2 charger only works with engine running. I’m almost certain this new charger has a low voltage cutoff that is set too high, like the DJI mavic pro car charger.

 

[Mr. Salty]

Keep in mind, the new batteries require a higher voltage than the Mavic Pro batteries do.

 

[sar104]

Keep in mind, the new batteries require a higher voltage than the Mavic Pro batteries do.

The charger up-converts to around 17.5 V, so that's not the problem. More likely it's the input voltage range, which is listed as 12 - 16 V. With the engine off and pulling 6 A or so, the battery voltage may sag below 12 V.

 

[DanMan32]

The stock car charger has the same issue. There's a YouTube video where someone tested it. It cuts out at about 11.3v but he saw a voltage drop of 0.5v between his testing power supply and the car outlet he was using when the charger started drawing 6A when the battery started actually charging. My calculations estimated wiring rest of 0.085 ohms.

 

[SteveCA]

The charger up-converts to around 17.5 V, so that's not the problem. More likely it's the input voltage range, which is listed as 12 - 16 V. With the engine off and pulling 6 A or so, the battery voltage may sag below 12 V.

i’m sure you are right. I’m going to check the voltage sag with my voltmeter next time. In any event, the cutoff is too high to be useful.

I’ve charged 6s lipos for my rc helicopters in this truck without issue for years using a quality lipo charger but that was directly connected to the battery and the low voltage cutoff was set to 11 volts.

 

[DanMan32]

In any event, the cutoff is too high to be useful.

Agreed. However some cars may have a weak battery that after a short time at that large current draw may render the car unable to start. I had that issue with my last Accord I bought used from the dealer.
It was fine after replacing the car battery.

 

[AForceone]

As much power as these battery need to charge, there is no way to run them when the car is off. In fact, you may need to turn on the headlights to "kick" the alternator into producing more power. Some Smart chargers (not sure if this one is or not) would stop charging if the battery falls below 12.5V (to make sure you can start your car and not drain the battery).

 

[Paul2660]

My 4-runner has the ability to charge with a AC port, but for anything of serious size, laptop, or a DJI chargers I have to have the engine running. You will get a yellow light on the button on the dash where you enable the AC port if you are trying to charge without the engine running, light should be green. This is a 2010 4-runner. so things may have changed in 8 or so years.

Paul C

 

[SteveCA]

As much power as these battery need to charge, there is no way to run them when the car is off. In fact, you may need to turn on the headlights to "kick" the alternator into producing more power. Some Smart chargers (not sure if this one is or not) would stop charging if the battery falls below 12.5V (to make sure you can start your car and not drain the battery).

It depends on your vehicle. You are right with most passenger cars which have small batteries. Full size trucks, especially diesel trucks, have larger batteries, sometimes two large batteries and they are more than capable of charging these drone batteries. My truck, which has two large batteries, have no issues charging (with the engine off) much larger 6s Rc helicopter Lipos, at a much faster rate to boot. Bottomline is this charger has a voltage cutoff that is set too high, likely 12.5 to 13 volts...

 

[Above]

I use a power inverter in my cars for flight days. Much easier to charge all the stuff I need to charge. The inverter has a low voltage alarm so I know when to start my car so I dont end up stranded........ but I also have a lipo jump pack for starting dead cars and charging things when I'm hiking and away from power.

 

[kilomikebravo]

I have have a diesel GMC with dual batteries.

I don't know about GMC diesel trucks but I've been told by Ford that my F-250 uses one battery solely for starting and the second for normal battery duties. Und zo, I don't THINK your truck would use both to run the charger whether the engine was running or not. That said, I haven't crawled under mine to see which battery cable(s) go to the starter.