Power Bank Charging Question, do I need to disconnect the input lead when the engine is off?

[Submariner Gold]

Firstly apologies for the detail ... but I wanted to explain fully
I don't think my TQKA battery supports “pass through charging”.

How my set up works, when the engine runs, it powers the dual USB charger [glows blue]. This sends power to the Camera cable-lead on the left, and to the Battery’s charging input on the right [it energises the battery meter and shows % charge in a red LED].


Obviously when the engine is off, there is no power to run the camera or charge the Battery, per below


When I want to run the camera in “Parking” mode, and the engine is off
I need to manually unplug the cable connected to the camera from my left USB port, and insert it into one of the Battery’s 5V outputs Like below:-

I can see the battery LED is activated, and the power starts the camera. Naturally with the engine off there is no power from the USB Port.

So I assume the battery is not being charged and discharged at the same time ( not yet been confirmed by the Mfg. if this is allowed, with this battery ).

My questions are
Q1. “do I need to physically undo the cable from the right USB chanel (the cable that is normally used to charge the Battery) , when the engine is off, and I use the battery for Parking mode? (Note at this moment we are not charging the battery)

Q2. I am assuming power can’t leak out of the battery's charging input terminal, and reverse back into the dormant USB charging port? I.e when the engine is off, and I am draining battery power to run the camera.

Trying to double check power wouldnt reverse out of the charging input.
I connected a USB meter, but I am not sure if this is a vald test; as I had to connect the meter the wrong way around, i.e. I would really need a Micro B meter. But maybe it would tell me if the power was present in the input charging cable?? But not too confident of this.

As you can see, the meter doesnt turn on. But I really dont know if this is a valid test.

Naturally my main issue is , do I have to undo this cable?, its bad enough having to swap the dashcsm cable

i did notice, that the USB port could occaisionally output up to 5.15V , is this too high for the camera? I assume its OK , as the USB spec is up to 5.25V; and I suspect the Volts may drop by the time they have travelled 4M to the camera?

Most of the time, it runs more like 5.11V .

 

[Nigel]

My questions are
Q1. “do I need to physically undo the cable from the right USB chanel (the cable that is normally used to charge the Battery) , when the engine is off, and I use the battery for Parking mode? (Note at this moment we are not charging the battery)

No, there shouldn't be an issue, many people will do this and any issue would already have been fixed.

Q2. I am assuming power can’t leak out of the battery's charging input terminal, and reverse back into the dormant USB charging port? I.e when the engine is off, and I am draining battery power to run the camera.

The powerbank almost certainly doesn't put anything out of its input, it will only provide power to it's outputs.

Even if it did then it is unlikely that there would be a problem since the charger will be happy with 5V being put on its output. It is possible there would be a bit of wasted power which is why it is not recommended that you connect the camera output from the power bank directly to the camera output from the charger, you should use diodes, a switch, or swap the cables.

But maybe it would tell me if the power was present in the input charging cable?? But not too confident of this.

The meter is probably not designed to be used like that, but would probably work, be interesting to see if the amps value reads negative when you do this...

Naturally my main issue is , do I have to undo this cable?, its bad enough having to swap the dashcsm cable

Don't bother, nobody else would and I'm sure other people have tried.

i did notice, that the USB port could occaisionally output up to 5.15V , is this too high for the camera?

Anything within the USB spec is fine, just a little over can blow up the capacitors in some cameras, I wouldn't risk using anything that outputs more than 5.40V unless it was supplied with the camera. 5.15V is perfectly normal when there isn't much power being used.

I suspect the Volts may drop by the time they have travelled 4M to the camera?

Probably, but only if the camera is using power, when it is starting up and shutting down there will be times when it's not using much and so there wont be much voltage drop.

 

[Submariner Gold]

No, there shouldn't be an issue, many people will do this and any issue would already have been fixed.


The powerbank almost certainly doesn't put anything out of its input, it will only provide power to it's outputs.

Even if it did then it is unlikely that there would be a problem since the charger will be happy with 5V being put on its output. It is possible there would be a bit of wasted power which is why it is not recommended that you connect the camera output from the power bank directly to the camera output from the charger, you should use diodes, a switch, or swap the cables.


The meter is probably not designed to be used like that, but would probably work, be interesting to see if the amps value reads negative when you do this...


Don't bother, nobody else would and I'm sure other people have tried.


Anything within the USB spec is fine, just a little over can blow up the capacitors in some cameras, I wouldn't risk using anything that outputs more than 5.40V unless it was supplied with the camera. 5.15V is perfectly normal when there isn't much power being used.


Probably, but only if the camera is using power, when it is starting up and shutting down there will be times when it's not using much and so there wont be much voltage drop.

Thanks so much for your valued and much appreciated detailed response.

Re “The meter is probably not designed to be used like that, but would probably work, be interesting to see if the amps value reads negative when you do this...”
As per the picture above, the meter didnt even light up.

Obviously, if you meant, when I get proper USB micro meter and thus have it the right way around, I havent a clue.
And now feel confident enough to just leave the Battery “charging cable” attached when the engine is off , and I use the Battery to power the camera.