Charging P3 4k transmitter

[Moby58]

Hi Guys,

I am going to use a different solution to charge my P3 batteries, so dont need to use the stock charger.

However, I am going to need something to charge the transmitter batteries.

So, do I need to use a charger or a 12v power supply to charge the transmitter batteries?

If a charger, what are the details of the Tx battery??

 

[erlik-khan]

This is probably something you shouldn't do. Can i ask why you dont like the stock charger? I just got my phantom3 4k so i dont yet have my own opinion of the components.
You don't seem to have a good understanding of DC circuits "do i need a charger or a 12v power supply". So i wouldnt recomend trying to do this. The stock charger for the P3 4k has a 17.4v 3.3a output. But that is rated for charging BOTH, or either, the transmitter and flight battery. It would be hard to tell how much of that rating goes ONLY to the transmitter. You would need to find out exactly what power needs the transmitter has and find a power supply to match it exactly, or you risk ruining your transmitter battery. From the label on my p3 4k charger i cannot tell you exactly how much of that current is for the transmitter alone, so i cannot help you further. Look for documentation on the transmitter

 

[N017RW]

You're literally playing with fire.
The majority of LiPo accidents (fires) occur during charging.

 

[Moby58]

Thanks for the reply, but you REALLY should not make assumptions about someone's knowledge with statements like "You don't seem to have a good understanding of DC circuits "do i need a charger or a 12v power supply".

I have a VERY good knowledge. I have been doing radio control for around 40 years. I fly planes, helis, quads, race cars and model yachts. I have around 50 LiPo batteries in my collection.

So, reference my question.
In the early days, when radio transmitters had rechargeable batteries, You always used a charger to charge the batteries, as the connector on the radio was just simple wiring to the battery. You could never just plug in, say, a 12v power supply.

A lot of radios now (Like my FrSky Taranis and my Spektrum DX9) have built in chargers in the handset, that auto detect the battery chemistry (NiMh, LiPo, LiFe, etc) and adjust the charge rate and style accordingly. With these transmitters, you must plug in a 12v power supply, and never a charger.

As I use a different charging solution for my flight batteries, I want to use something different for the transmitter, to cut down on the wiring. I really dont want to pull the transmitter apart to see which way the batteries are charged, if I can find the correct answer on the net'

This is probably something you shouldn't do. Can i ask why you dont like the stock charger? I just got my phantom3 4k so i dont yet have my own opinion of the components.
You don't seem to have a good understanding of DC circuits "do i need a charger or a 12v power supply". So i wouldnt recomend trying to do this. The stock charger for the P3 4k has a 17.4v 3.3a output. But that is rated for charging BOTH, or either, the transmitter and flight battery. It would be hard to tell how much of that rating goes ONLY to the transmitter. You would need to find out exactly what power needs the transmitter has and find a power supply to match it exactly, or you risk ruining your transmitter battery. From the label on my p3 4k charger i cannot tell you exactly how much of that current is for the transmitter alone, so i cannot help you further. Look for documentation on the transmitter

 

[erlik-khan]

Moby58, i made an observation by saying you don't seem, instead of declaring it as fact, as to state that by your OP, you did not display an in depth knowledge of battery technology or any adequate research into the subject therein.

As the other poster has mentioned, battery charging mods is literally playing with fire. I was only trying to sway you from something that has no clear benefits as outlined by your OP but documented risk.

You said something about a 12v, but there isn't much evidence that anything would have to do with 12v, given the battery itself is a 15v and the chargers output is 17.4v. These are things i told you in my post and those are facts that i took the time to look up for you to help you since you apparently didn't. I took the time to try to help you so take it or leave it since you say you are highly educated in dc circuits you can figure it out yourself, why ask in the first place.....

 

[Moby58]

OK,

This can go on for ever, but I hope it doesn't. We both have better things to do (like getting selfish shots.... LOL)

If you refer to my original post, I stated that I only want to charge the transmitter battery.

And as I stated in my second post, transmitters today either have a built in charge circuit and only require a power supply (usually 12v), or the older style that require a charger.

There is no mention of 'moding' anything at all. Also, the 15v and 17 volt you refer to to is for the flight batteries and (I believe) not the transmitter

I didn't believe I needed to go into a 5 paragraph description of what I was gonna do, just to find out if the TRANSMITTER (only) requires a power supply OR a charger. I was hoping that someone else had gone same path and found out the definitive answer.

And for information, the 17 volt from supplied charger is actually (i beleive) just a straight 17v power supply (and not a charger output) as the charging and battery maintaining circuit is in the battery.

That is, you are not connecting a charger to your flight batteries, you are connecting a 17v power supply (and the battery does the rest).

I just want to know if I am connecting a power supply to the transmitter (and charge circuit is in transmitter), or am I connecting a charger to the transmitter (and charge circuit is not in the transmitter.

And just because we have had a rant at each other, don't let it stop you answering other (or my questions) . Everyone has something to contribute, and even this thread may very well get people thinking!!!

Moby58, i made an observation by saying you don't seem, instead of declaring it as fact, as to state that by your OP, you did not display an in depth knowledge of battery technology or any adequate research into the subject therein.

As the other poster has mentioned, battery charging mods is literally playing with fire. I was only trying to sway you from something that has no clear benefits as outlined by your OP but documented risk.

You said something about a 12v, but there isn't much evidence that anything would have to do with 12v, given the battery itself is a 15v and the chargers output is 17.4v. These are things i told you in my post and those are facts that i took the time to look up for you to help you since you apparently didn't. I took the time to try to help you so take it or leave it since you say you are highly educated in dc circuits you can figure it out yourself, why ask in the first place.....

 

[Mako79]

OK,

This can go on for ever, but I hope it doesn't. We both have better things to do (like getting selfish shots.... LOL)

If you refer to my original post, I stated that I only want to charge the transmitter battery.

And as I stated in my second post, transmitters today either have a built in charge circuit and only require a power supply (usually 12v), or the older style that require a charger.

There is no mention of 'moding' anything at all. Also, the 15v and 17 volt you refer to to is for the flight batteries and (I believe) not the transmitter

I didn't believe I needed to go into a 5 paragraph description of what I was gonna do, just to find out if the TRANSMITTER (only) requires a power supply OR a charger. I was hoping that someone else had gone same path and found out the definitive answer.

And for information, the 17 volt from supplied charger is actually (i beleive) just a straight 17v power supply (and not a charger output) as the charging and battery maintaining circuit is in the battery.

That is, you are not connecting a charger to your flight batteries, you are connecting a 17v power supply (and the battery does the rest).

I just want to know if I am connecting a power supply to the transmitter (and charge circuit is in transmitter), or am I connecting a charger to the transmitter (and charge circuit is not in the transmitter.

And just because we have had a rant at each other, don't let it stop you answering other (or my questions) . Everyone has something to contribute, and even this thread may very well get people thinking!!!

I can't tell if the transmitter is regulating the charge or not. Not many people here would do a mod like this. You are correct that the flight batteries are self regulated by an onboard computer. I've seen pilots use 12V car batteries and wire it directly to the terminals to get them out of trouble.

Anyways...
Get a voltmeter and see how much the charger is actually outputting to the plug. If its 17V, then you could getaway with using 15V (or maybe a 12V) charger. You can only damage it if you use anything over 17V or if you get the polarities wrong.

 

[N017RW]

IIRC it's a 2S LiPo in the Tx/controller.

 

[erlik-khan]

Moby58, i don't think you read my posts accurately. I didn't say anything about the 17v being "a charger". I was just pointing out that from the rated output listed on the power supply that the P3 came with, it is hard to determine how much is going to the transmitter. Also, the p3a is advised not to charge both the transmitter and flight battery at the same time, meaning its even more difficult to figure out the specs for the transmitter from just looking at the power supply.

I was also trying to prevent you from possibly injuring yourself or others. You asked for advice, i took the time and gave you my opinion that's all.