A USB Power question, could I use this USB Splitter

[Submariner Gold]

Just came across this product ... originally designed so two PCs can share a USB device. Think of the PCs as. Power sources.
UGREEN USB Switch, 2 Port Scanner Printer Share Switcher Selector Box Hub with 2 pcs of USB 2.0 A to A cables for Scanner,Printer Mouse,Keyboard etc. https://www.amazon.co.uk/gp/B01CU4QCRS

I have ordered one of these to provide a 2 port USB outlet wired to my Acc. ign. + cigar lighter fuse, via a piggy back fuse holder.
CHGeek Dual USB 4.2A Charger Socket 12V/24V Waterproof Power Outlet for Car Boat Marine Motorcycle (4.2A-Blue) https://www.amazon.co.uk/gp/B075YP9TD1


And my new 20,000 mA power bank with two 5V 3.1A outlets arrived today.
Tqka 20000mAh Portable Charger, 3.1A Dual USB Output Smart Charge External Battery, Ultra High Capacity Power Bank with LED Digital Display for iPhone, iPad, Samsung and More - Black https://www.amazon.co.uk/gp/B073QQPKVY

Could I connect one of the 2.1A outlets from the Dual USB charger, to the PC 1 input on the USB switch. And connect the other outlet from the USB charger to the charging input on the Tqka power-bank.

Then connect one of the Tqka Powerbanks 3.1A outlets to the ‘PC 2’ input on the USB switch.
Also connect the output of the USB switch to the Dashcam ( that needs 5V 1A).

The result is the USB Switch has one Acc. Ign. Switched 5V 2.1A going to PC1. And a Battery powerbrick 3.1A source going to PC2.
And the second USB output from the USB charger supplies power @ 2.1A to the Tqka power-bank’s charging input (max rating 2A)..
[Note I dont think the Tqka supports “pass through charging”.]

Proposed Working Practice:-
Normally I will leave the USB switch on position PC1 i.e. when driving the power to the Dashcam is supplied by the ign. Engine circuit.
And at that time it also charges the Powerbrick ( note as the switch is in PC1 position ) no power is drawn from the powerbank as it is being recharged.
(Note when the Tqka is fully charged at 100%, it stops taking any more power ... well it does on the wall charger).

Occasionally when I want to have Parking-mode on. I.e. engine is off. All I have to do is press one button on the USB switch to select PC2
Then power is sourced from the battery.
Note as the engine is off, the Tqka battery stops being charged. So no need for pass through.

One risk is I come back to the car, when its in PC2 position i.e. draining my powerbank, and forget to switch back to PC1 !!
Then I might have an issue, as the powerbrick would be charging and delivering power!
But it avoids pulling out Fragile USB connectors.

The second risk is ... how good is this switch, i.e does it instanly disengage properly before contacting the other source. One would hope so. But I will test that off the car first.

Q. If there was a very short time lag, could this wreck the car i.e. momentarily positve from the powerbank battery could contact the power coming from tne ign. Circuit albeit via a converter from 12V to 5V , I assume that wouldnt happen. I.e. could it reverse convert?? Or whatever hopefully those diodes are one way.

The third risk, which I need advice on is this USB switch says its for USB 2.0. But as its switching to things like printer that have their own power, does it switch power as well as data?

And then there is the big walnut. USB 2.0 is only rated at 0.5As, even USB 3.0 is only rated at 0.9A, admittedly thats what it can provide;
Q. but can this USB switch safely pass 2.1A or 3.1A (namely the power supplied by my USB charger socket and powerbank respectively) ?
Or would it only have to take 1A through it, i.e. for the Vico MF3 or 1.5A if I upgraded to the new NB 612GW?

If only they made a USB 3.0 varient that supported high speed charging.

I guess I could ask them

Q. If the USB switch wouldn't take over 0.5A, would this USB switch, limit the power throughput to USB 2 levels? ( maybe even stopping the dashcam working) or would it melt?

Obviously if this all panned out it looks like a fairly sweet solution to using powerbanks and ad hoc parking mode, at the press of the button.

Any flaws in my logic please let me know.

I guess I could downgrade it , and forget in- car charging of the power bank. And just connect the second USB socket on the USB charger to a rear dashcam.

However if this USB switch could handle the power, or they made a USB 3.1 version that could handle 1.5A and 3A this could be an OK solution.

 

[Submariner Gold]

Any views on this USB switch?
And the associated power carrying capability?

 

[Nigel]

Looks like it probably would work, but I can't tell what is inside it just from the advert.
I guess it just has a mechanical 4 pole 2 way switch in it.
You could just buy the switch to add to your dash, eg: https://www.ebay.co.uk/itm/350998531031
However most of these switches, including that one are not rated for a lot of amps, which makes me doubt if the your USB switch would be rated for more than standard USB current, and also the ones with low current ratings may loose too many volts due to contact resistance and the dashcam may decide to shutdown as a result, I wouldn't be surprised if that happened with your Amazon switch.

Maybe better just to buy a standard 2 pole power switch and directly solder it into your USB cables.
EG: https://www.ebay.co.uk/itm/272780210800
That has a 3A DC contact rating so should be fine.

 

[Submariner Gold]

Thanks Nigel,
I didnt want to touch the dash, as some folling buyers are very keen on bog standard and there are no add on seperate bits on a S Class coupe its one incredibly long part.

I too was worried this switch would only be rated for standard USB Current.

And USB is a nightmare in itself. When I built my workstation (yes you may well laugh yourself silly ... can you imagine me investigating NVME PCIe SSDs) , but I managed that ... struck lucky with a Supermicro server board and Xeon CPU that supports the Intel 750 SSD range ... how, why, ? it works ... who cares when it reads 22,000 MB/s and boots Win 10 in 8.9 secs to usable

but boy was I so ,so , so confused with USB.
There seemed to be very confusing standards.
I think current (Amps) wise they are :-
USB 1 and USB 2 = 0.5A
USB 3 = 0.9A
But then they talk about a differentiating between a ‘Downstream Port’ and a ‘Downstream Charging Port’ and then Ports that support Super Speed, which I think ? carry 1.5A.
Apparently the USB 3 Downstream Charging Port = 1.5 A but that could be if they have an SS on them??
and USB 3.1 Downstream Charging Ports = 1.5 A and or 3A
Not sure how you tell if something is a Downstream Charging Port?

So quite frankly in my laymans opinion, its a seriously crap standard, and highly confusing .
Who would bet their life they could tell what current any given USB port could support.
- there would be a lot of dead bodies, if they took the challenge

why on earth did Vicovation and most others choose a Micro B input, other than to try and pick the tiniest pins possible so they break/burn out; and we have to buy a new dashcam.

So I guess it depends is this switch a Downstream Charging Port with Super speed.
As its designed for 2 PCs to share a device lets hope they had portable discs in mind and let it pass 1.5A??

I so wish someone made a cheap (£20-£30) 12V External Battery bank, with a couple of 12V dc outputs. :-/


In the end on the Workstation I went for 6x USB 3.1 Downstream Charging ports able to deliver 3.0A. And 4x USB C Ports. ... I think they said they supported PD ?? Some power delivery std. ? So I think those type C are even up to 5A .. but no idea really. They were just selected to kinda future proof it.

 

[dzal67]

I wonder if that would work

 

[Nigel]

I wonder if that would workView attachment 35860

Problem with that is that you will loose some voltage across the diodes and if you loose too much then the camera will not be happy. Otherwise it is correct, you need the diodes because otherwise some of the battery power will get lost going backwards into the charger.

Better off with a relay that connects the battery when off and switches to the charger when on, powered by the charger, the camera wont mind the short disconnection while switching.

 

[Deleted member 37895]

I don't think that connection setup would be a good idea. It's simpler to just use a power bank with passthrough charging.

There is discussion in this thread https://dashcamtalk.com/forum/threads/battery-pack-with-12v-socket-plug-in.21939/page-8#post-387290

The PowerAdd unit discussed there, which I bought, does support pass through according to the seller on Amazon but it's not explicitly stated in the description. I tried it with mine and it does seem to work fine. It has 3 USB outputs and 2 USB inputs. Combined charging wattage should be about 20 watts. So let's say your camera uses 5 watts. That means 1 hour of driving should provide enough charge for 4 hours of recording

You might want to get one of these to protect the powerbank from the voltage drop when starting the car... It delays the power to USB and cigarette lighter sockets by 10 seconds. I have one and I wish the delay was shorter, 1 second would be fine. But it does do what it says https://www.amazon.com/gp/B0755BRRFS

 

[dzal67]

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

 

[Nigel]

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

Can you solve the problem by permanently pressing the ON button?

 

[dzal67]

Can you solve the problem by permanently pressing the ON button?

That was my first thing to try. Nope. It has to have some logic board inside not just on/off switch.

 

[Submariner Gold]

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

Hmmm I noticed that and put it down to some glitch with my cheap USB meter, ordered another meter to solve it.
I dont think one can charge these and drain power at the same time.
So on mine just doing the physical connection fires her up into charge mode. I think but will double check

 

[Deleted member 37895]

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

I have had several power banks in the past like that. They usually don't tell you in the product description.

The MyCharge rugged powerbanks that Best Buy sells will turn on as soon as a device is plugged in. The PowerAdd powerbank I mentioned above will also work

 

[dzal67]

Today I tried my new power bank by connecting camera to it. Results are no bad so far. In 12 hrs ( 9.5 hrs in parking mode ) and according display on battery it used only 31 % . I think it is good for $ 22 battery pack.

 

[Nigel]

Today I tried my new power bank by connecting camera to it. Results are no bad so far. In 12 hrs ( 9.5 hrs in parking mode ) and according display on battery it used only 31 % . I think it is good for $ 22 battery pack.

If you want to record for 24 hours, how much of that time do you need to be driving so that it has enough charge for the rest?

 

[Submariner Gold]

Today I tried my new power bank by connecting camera to it. Results are no bad so far. In 12 hrs ( 9.5 hrs in parking mode ) and according display on battery it used only 31 % . I think it is good for $ 22 battery pack.

I have yet to test mine ( awaiting 4m usb cable .. power bank to camera)
I noticed when connecting my power bank to camera on ashort cable it used 0.5A.
So I assumed as its a 20,000 mA battery it would last slightly less than 40 hours, before it was totally flat.

At your figures then theoretically 0% should give me/you? 38.7 hours ( 100/31 * 12)

Obviously I guess it will power off, some time before its flat.
But in your scenario. For my camera therefore24 hours might run it down to 38%.
That would do me nicely for £19!
I rarely envisage needing running for more that 12 hours in a rough area

 

[Submariner Gold]

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

I just purchased Tqka 20000mA battery pack and it cannot be used how I planed. Problem is that once pack is disconnected from charger, it won't start charging device connected to it until ON button is pressed. My other, smaller pack does it automatically: once power to bank is turned off it starts powering device connected to it.

Hi
I started a dedicated thread for TQKA 20,000 mA Power bank users .. be nice if youU would join in
https://dashcamtalk.com/forum/threads/official-owners-thread-tqka-20-000-mah-lifepo4-battery.32838/

Plus put a cheeky question to you.
Thanks Peter

 

[Nigel]

I noticed when connecting my power bank to camera on ashort cable it used 0.5A.
So I assumed as its a 20,000 mA battery it would last slightly less than 40 hours, before it was totally flat.

Probably about 30% less.

The 20,000mAh figure is normally based on the capacity of the lithium battery cells and they run at 3.7 volts. You are measuring the camera at 5 volts which contains more power per mA.

 

[Dashmellow]

I have yet to test mine ( awaiting 4m usb cable .. power bank to camera)
I noticed when connecting my power bank to camera on ashort cable it used 0.5A.
So I assumed as its a 20,000 mA battery it would last slightly less than 40 hours, before it was totally flat.

At your figures then theoretically 0% should give me/you? 38.7 hours ( 100/31 * 12)

Obviously I guess it will power off, some time before its flat.
But in your scenario. For my camera therefore24 hours might run it down to 38%.
That would do me nicely for £19!
I rarely envisage needing running for more that 12 hours in a rough area

Depending on the manufacturer, the low voltage protection circuit of a Li-ion power bank cuts off when the cells are between 2.2V and 2.8V. Lithium cells that drop below that will be damaged.

Running a power bank until flat (cut-off) on a regular basis will significantly shorten its lifespan but some may find that a reasonable trade-off.

 

[Dashmellow]

Can you solve the problem by permanently pressing the ON button?

That was my first thing to try. Nope. It has to have some logic board inside not just on/off switch.

It has a momentary switch. A brief press will switch the power bank on and depressing the button for 2 seconds will switch the unit off.

 

[Submariner Gold]

Depending on the manufacturer, the low voltage protection circuit of a Li-ion power bank cuts off when the cells are between 2.2V and 2.8V. Lithium cells that drop below that will be damaged.

Running a power bank until flat (cut-off) on a regular basis will significantly shorten its lifespan but some may find that a reasonable trade-off.

Are LiFePO batteries supposed to be better, the same or worse than Li ion batteries (when deep discharged) ?