Will this draw any power if I leave it plugged

[Erci]

Re: Will this draw any power if I leave it plugged in

Erci, I stayed at a Hoilday Inn last night so here's the straight story.

Your screwed... the only way you can fix such a big screw up is to ride your bike to California where Cliff and I can visually check this device. After several runs up and down Montezuma Rd. we will be able to determine the answer to your question.

Until then don't sweat it, leave it plugged in a few weeks without riding and try to start the bike

Glad I could help!

LMAO! I'm gonna try to run that explanation by my wife and see if she gives me the OK :rof:

 

[Motogiro]

Re: Will this draw any power if I leave it plugged in

If you have a completely discharged battery, how close to a 'short' does that look to the voltage source?

My concern has more to do with recharging batteries without damaging them than operating a device with a full charge on it. NiCad, NiMh, Li, all have different charging characteristics. Most can accept a low current intake without damage..... 20X the possible current may mean that the battery can suck up juice 20X faster than the device mfg allowed for....

If the gizmo plugged into the port has no current regulation circuitry of it's own, and is expected to be limited by the USB port itself it can draw much more current much more quickly than anticipated.

Do you think it likely that a gizmo sold online as cheaply as this one has current regulation built in? When it states that up to 2 Amperes are available on one port? I'd HOPE a $2-500 phone would be able to limit it's intake current....

Oh yeah I see what you mean. I thought you were talking about current delivery from the 12 volt source. Usually the Lith-ion battery side self regulates so it should only use that amount of current and be done when it's topped off...

 

[RJ2112]

Re: Will this draw any power if I leave it plugged in

Oh yeah I see what you mean. I thought you were talking about current delivery from the 12 volt source. Usually the Lith-ion battery side self regulates so it should only use that amount of current and be done when it's topped off...

I agree, the current consumption of this gizmo with nothing plugged into it is probably quite low. I'd think similar to the LCD display's consumption, or less.

The 12V to USB converter appears to be limited to a maximum of 10 Watts, if it can deliver 2 A @ 5 VDC.

That means the 12V side input to the converter can't exceed ~ 0.8 Amperes. (there will be a bit of loss on the conversion, so it would be on the higher side of that 0.8.)

If this thing is fused to allow less than 2 A on the output, it would be safer for downstream USB devices.

With the fuse on the 12V input side I would suggest a .125 A fuse. 1/8 A input max, would allow a bit more than 1/4 amp on the 5 VDC output side. That would still be enough 'juice' to support 2 USB ports at full power (0.1 Amperes allowed). Anything over that amount would have to become heat, at some point.

Call me a belt and suspenders kind of guy -- I don't like having my electronics fail. Especially if it's due to something I could have avoided.

 

[Motogiro]

Re: Will this draw any power if I leave it plugged in

I agree, the current consumption of this gizmo with nothing plugged into it is probably quite low. I'd think similar to the LCD display's consumption, or less.

The 12V to USB converter appears to be limited to a maximum of 10 Watts, if it can deliver 2 A @ 5 VDC.

That means the 12V side input to the converter can't exceed ~ 0.8 Amperes. (there will be a bit of loss on the conversion, so it would be on the higher side of that 0.8.)

If this thing is fused to allow less than 2 A on the output, it would be safer for downstream USB devices.

With the fuse on the 12V input side I would suggest a .125 A fuse. 1/8 A input max, would allow a bit more than 1/4 amp on the 5 VDC output side. That would still be enough 'juice' to support 2 USB ports at full power (0.1 Amperes allowed). Anything over that amount would have to become heat, at some point.

Call me a belt and suspenders kind of guy -- I don't like having my electronics fail. Especially if it's due to something I could have avoided.

I agree with avoiding your electronics failing. I'm thinking the USB converter is fused and regulates maximum useable power within it's own current limitations and specs. It never hurts to protect your gear and circuits but in this case I think it's pretty safe between the design of the USB converter with it's own internal current limitation and the device's regulation being charged.

In Erci's case he wants to know if his battery is being drained leaving the USB plugged in.
I do have one of those USB converters and although probably not the same manufacturer, it's probaby close to the same circuit if not the exact same IC type 5 volt regulator. If I get a chance I'll do an idle current draw test on it today and post my finding.

 

[Erci]

Re: Will this draw any power if I leave it plugged in

In Erci's case he wants to know if his battery is being drained leaving the USB plugged in.
I do have one of those USB converters and although probably not the same manufacturer, it's probaby close to the same circuit if not the exact same IC type 5 volt regulator. If I get a chance I'll do an idle current draw test on it today and post my finding.

I'll have the amp meter tomorrow. I'll test it then and I'll post my findings :thumbup:

 

[Erci]

OK.. I'm painfully useless at this

I tried the clamp (amp meter) over hot wire in all settings, with my phone plugged in and charging. Not a friggin thing.. no reading in any setting.

I went back to my old DVM and tried Cliff's suggestion.. still not getting anything. No idea why, but it would not complete the circuit. I basically pulled the fuse and used the DVM *instead* of the fuse. The only way I managed to get any reading was this: I set it to 2v and held both pins to ends of my inline fuse (red pin to one end and black pin to the other end). It showed .002 with cable plugged into the phone. With cable unplugged from phone, reading went back to .000.

 

[metallicat]

OK.. I'm painfully useless at this

I tried the clamp (amp meter) over hot wire in all settings, with my phone plugged in and charging. Not a friggin thing.. no reading in any setting.

I went back to my old DVM and tried Cliff's suggestion.. still not getting anything. No idea why, but it would not complete the circuit. I basically pulled the fuse and used the DVM *instead* of the fuse. The only way I managed to get any reading was this: I set it to 2v and held both pins to ends of my inline fuse (red pin to one end and black pin to the other end). It showed .002 with cable plugged into the phone. With cable unplugged from phone, reading went back to .000.

Not following you 100%, but if draw is 000 disconnected you're probably good to go . You may have some setting off on the meter... some are overly complex for this purpose. Try to measure voltage (not amperage) and see what it is before you plug in, after, and again before [unplugged]. You can even measure the battery terminals directly.

Did I mention you're probably good to go based on what you said?

 

[Erci]

Not following you 100%, but if draw is 000 disconnected you're probably good to go . You may have some setting off on the meter... some are overly complex for this purpose. Try to measure voltage (not amperage) and see what it is before you plug in, after, and again before [unplugged]. You can even measure the battery terminals directly.

Did I mention you're probably good to go based on what you said?

I got this cheapy one. It's pretty simple and I did try the dial in all settings

 

[Motogiro]

I got this cheapy one. It's pretty simple and I did try the dial in all settings

This is for measuring household alternating current and won't measure DC current.

Use your digital multimeter by selecting the DC amperage mode. It should say mA on the readout signifying milliamps. Depending on the meter you may have to switch the red lead to a different plug on the meter where it can read amperage. Open the positive wire on your accessory plug Then put the red and black wires inline to complete the circuit so that the meter is in series so that current can now pass through the meter. I won't matter which polarity with the digital volt meter and if it backwards the readout will just show a minus (-) sign but the current reading will be accurate. You should be able to see a reading with your phone plugged in.

You need to establish that your meter is getting a measurement before you can deduce whether there is current flowing with just your idle USB device plugged in.

Hope this helps...

 

[Erci]

This is for measuring household alternating current and won't measure DC current.

Use your digital multimeter by selecting the DC amperage mode. It should say mA on the readout signifying milliamps. Depending on the meter you may have to switch the red lead to a different plug on the meter where it can read amperage. Open the positive wire on your accessory plug Then put the red and black wires inline to complete the circuit so that the meter is in series so that current can now pass through the meter. I won't matter which polarity with the digital volt meter and if it backwards the readout will just show a minus (-) sign but the current reading will be accurate. You should be able to see a reading with your phone plugged in.

You need to establish that your meter is getting a measurement before you can deduce whether there is current flowing with just your idle USB device plugged in.

Hope this helps...

Thanks, Cliff! Definitely helps and I did try to do just that, last night. I'll try again tonight after work and I'll post a pic of exactly how I'm trying to measure it (cause I got no reading yesterday and wasn't able to complete the circuit)

 

[ChevyFazer]

Man I'm sorry for even suggesting the amp meter i feel like a jackass I had no clue it wouldn't read dc current...

Lol like I said though I know just enough to get myself into trouble....

 

[Erci]

Man I'm sorry for even suggesting the amp meter i feel like a jackass I had no clue it wouldn't read dc current...

Lol like I said though I know just enough to get myself into trouble....

No worries, man. It was only $15 and I can (and probably will) return it.

 

[Erci]

Use your digital multimeter by selecting the DC amperage mode. It should say mA on the readout signifying milliamps. Depending on the meter you may have to switch the red lead to a different plug on the meter where it can read amperage. Open the positive wire on your accessory plug Then put the red and black wires inline to complete the circuit so that the meter is in series so that current can now pass through the meter. I won't matter which polarity with the digital volt meter and if it backwards the readout will just show a minus (-) sign but the current reading will be accurate. You should be able to see a reading with your phone plugged in.

You need to establish that your meter is getting a measurement before you can deduce whether there is current flowing with just your idle USB device plugged in.

Hope this helps...

First picture shows interrupted positive wire, with the 2 pins connected in-line to complete the circuit. This isn't working. Note the blue error pointing to LED light which stays off.

Same setup, but wire now has solid connection (as if I'm simply touching both pins to uninterrupted hot wire). Note that LED light is now on, but reading is still 0 (which answers my original question.. it's not drawing anything significant enough).

I am not getting any reading at all in mA mode. I can only get a reading in v mode (2v) with GPS plugged in.
So am I doing something wrong still? Why won't it complete the circuit via DVM? :don'tknow:

 

[edgeofnj]

i can't tell from the pictures for sure, but it looks like your meter only goes up to 200mA, which may be too low for that circuit. when i was hooking up my usb power, i bought a multimeter from home depot that measures DC current up to 10A just to test the circuit.

going back to your initial question - i would venture to guess that it will draw a small bit of power, similar to how adapters/converters left plugged into the wall still have vampire draw, since it's converting 12V to 5V. especially with inexpensive devices, i wouldn't expect them to have the "smart" components to disconnect in a lack of demand situation.

 

[Motogiro]

i can't tell from the pictures for sure, but it looks like your meter only goes up to 200mA, which may be too low for that circuit. when i was hooking up my usb power, i bought a multimeter from home depot that measures DC current up to 10A just to test the circuit.

going back to your initial question - i would venture to guess that it will draw a small bit of power, similar to how adapters/converters left plugged into the wall still have vampire draw, since it's converting 12V to 5V. especially with inexpensive devices, i wouldn't expect them to have the "smart" components to disconnect in a lack of demand situation.

Yes, the meter may be in the wrong range. Try a different range.

Yes, the only way to really tell is to measure this to see if there is current draw in the idle mode.