Parasitic power draw?

fozrider

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I've now hooked up the system as per the instructions. I'm using a Denali Powerhub with a switched and non-switched fused power source. I hooked the yellow wire to the switched side and the red wire to non-switched (always on), and of course the black to ground. The power LED has a very faint pulsing signal even when the bike is turned off and the Can-bus is inactive. How much power will this draw? For long term storage of the bike I will pull the fuses, but I don't want to do this if I'm not riding for 3 -4 weeks.
 
The power LED has a very faint pulsing signal even when the bike is turned off and the Can-bus is inactive.
Did you plug the GPS module into the DVR unit?
Give it a try without plugging the GPS module if yes!
How much power will this draw?
About 20mah~30mah
For long term storage of the bike I will pull the fuses, but I don't want to do this if I'm not riding for 3 -4 weeks.
Best to plug the fuse if without usage for a long time! Anyway, its hardwire kit has the low-voltage-protection for the battery!
 
Yes the GPS unit is plugged in. I might see how the battery voltage drops after a few days of inactivity. Test ride tmw!
 
The current hardwire kit cut-off voltage value set to be 11.4V. It should be okay to protect your motorcycle battery!
 
That's pretty low. I'll see what it draws over a few days, otherwise I'll put the trickle charger back on it. Hopefully it won't throw an error. My alarm system does cause an error on the charger.
 
I have now measured the power draw with the bike off to be about 40 mA. This is too high for my liking. Why is it so high? Is it the GPS add-on module? I pulled the fuse for just the B1M red wire and all other draws are reasonable (below 2.7 mA). The B1M red wire circuit peaks over 300 mA and then settles down to between 39 and 42 mA.

Is the purpose of the always on red wire to simply charge the internal battery? What would happen if I put both the yellow and red wires on the switched side?

My motorbike battery is 11 AH, therefore a 40 mA draw will use .04 x 24 = 0.96 amps per day. 11 Ah / 0.96 = 11.45 days before the battery is completely discharged. How long would it take to get down below 12.4 V? I'm not happy with discharging to 11.4 V on a regular basis.

So I pulled the GPS from the unit. It does the same start up peak then settles down to a decreasing mA from 25 to about 21.5 mA when I stopped.
 
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My motorbike battery is 11 AH, therefore a 40 mA draw will use .04 x 24 = 0.96 amps per day. 11 Ah / 0.96 = 11.45 days before the battery is completely discharged. How long would it take to get down below 12.4 V? I'm not happy with discharging to 11.4 V on a regular basis.
Do you think it will be a better solution to offer a hardwire kit with an adjustable cut-off voltage, from 11.8V to 12.4v?
And we can send you a hardwire kit for testing!
 
So I pulled the GPS from the unit. It does the same start up peak then settles down to a decreasing mA from 25 to about 21.5 mA when I stopped.
Maybe the built-in battery in charging after ignition off! You can have a check again after a few minutes!
 

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Do you think it will be a better solution to offer a hardwire kit with an adjustable cut-off voltage, from 11.8V to 12.4v?
And we can send you a hardwire kit for testing!
Indeed a hardwire kit with an adaptable cut off would be a very good idea. I'll PM you again. The bike has been on a charger overnight and the battery is now at 100% I'll do another test later today to see how the amp draw (and battery voltage) declines over time.
 
most motorbikes have very small batteries, they would reach 11.4v (which is also too low) too quickly, higher voltage cutoff options would be a good idea

Agree completely. Most motorcycle batteries simply do not have enough capacity to do any parking mode for more than an hour or so when new, and less when they age (and motorcycle batteries age faster than car batteries do). I think the best approach would be to have a separate powerbank type device for that, which could be set up "plug-and-play" style into a single added port in the main box where it could use the cam's power connection to charge up while riding, similar to how the Cellink device functions but a single wire install.

Phil
 
B1M disabled the parking mode on purpose, but it will drain the battery if without usage for a long time. So, we would like to set up a cut-off value for the power adapter to protect the motorcycle battery!
So the question is what is the ideal cut-off value for the power adapter :)
 
IMHO 12.4V for safest, but this will cut off quickly. 12.2V would be as far as I would dare stretch it. AGM batteries could take more but so many L/A batteries are still in use that you need to use them for standard reference values,.

Phil
 
B1M disabled the parking mode on purpose, but it will drain the battery if without usage for a long time. So, we would like to set up a cut-off value for the power adapter to protect the motorcycle battery!
So the question is what is the ideal cut-off value for the power adapter :)
if there is no parking function (should not offer this on a motorbike cam anyway so that's a good thing) and you just want the power supply to switch off afterwards then 12.4v is a better option, majority of bike batteries have very small reserve capacity, just make sure it has a time delay at that voltage before it cuts off as some bikes can drop voltage when just sitting idle but will safely be above that when they're moving, eg if voltage reaches 12.4v for a period of 90 seconds, then the cutoff works, if the voltage goes back above 12.4 before the 90 seconds then no cutoff
 
I think a better plan is that if the voltage rises by 0.3V above the lowest it has been then you turn on, and if it falls by 0.3 below the highest it has been then you turn off, both only after 90 seconds. Also it should always be on above above 12.8V

A full good battery should be about 12.7, you don't want it to drain below that, but if the battery is empty, maybe 11.7 then with a small alternator it may take some time to charge up to 12.4 and even longer to reach 12.7. Just using a fixed voltage will have problems.
 
I think a better plan is that if the voltage rises by 0.3V above the lowest it has been then you turn on, and if it falls by 0.3 below the highest it has been then you turn off, both only after 90 seconds. Also it should always be on above above 12.8V
sounds good in theory but which solution are you using to achieve this?
 
sounds good in theory but which solution are you using to achieve this?
How to implement it wasn't part of the question!

I think there should actually be no need to implement a voltage based turn off, because there is an input from the ignition switch, so without any parking mode it can go to zero power draw as soon as the ignition input is turned off, or at least put the processor in standby and draw a few micro amps.

On the Viofo MT1, after the the ACC input goes to zero, my multimeter reads 0.00mA through the red power connection.
 
How to implement it wasn't part of the question!
yeah coming up with an idea when there isn't an existing solution they could use to achieve it from their supplier just means longer lead time and greater expense to build something

whether or not it could use whatever method is used on the MT1 may come down to hardware but could also be a consideration
 
if there is no parking function (should not offer this on a motorbike cam anyway so that's a good thing) and you just want the power supply to switch off afterwards then 12.4v is a better option, majority of bike batteries have very small reserve capacity, just make sure it has a time delay at that voltage before it cuts off as some bikes can drop voltage when just sitting idle but will safely be above that when they're moving, eg if voltage reaches 12.4v for a period of 90 seconds, then the cutoff works, if the voltage goes back above 12.4 before the 90 seconds then no cutoff

I can't see a practical way to do any better than this. The hardware/software already exists for it, and it's very adequate for the job at hand. Motorcycle batteries are very minimal because of size and weight considerations whereas most car batteries can have more 'excess' capacity without such tight constraints on size and weight.

It's been some years, but back in the 90's when I worked on bikes batteries were a hot seller and rarely lasted more than 2-3 years on most bikes even when well-cared for. It was probably our thrid most frequent repair after tires and brakes or tune-ups.

Phil
 
I believe there should be a short time delay and then the unit should completely power off. My battery (a few years old now) reads 12.68 V at the terminal when fully charged but only 12.48V at the Denali powerhub, where I have the B1M unit hooked up. So there is a voltage drop due to distance and wire size. If the function of the constant power draw is to keep the internal clock charged, well I think 32 mA is too much. Surely the internal clock battery would last quite a while and could be recharged whilst riding. At the moment I park my bike in the garage so I'll just attach the trickle charger. However I'll try moving the constant power lead over to the switched side and see what happens to the unit on power down. If I lose the last file that's probably fine.
 
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