Mobius Super Capacitor.

2000rpm

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a battery, even when almost flat, has enough reserve power to power the camera while starting the vehicle when the voltage cuts

with caps, if they haven't charged sufficiently and you cut power (remember this is typically with a few seconds of receiving power) the camera will shutdown and not restart (already a problem for some users with caps) or corrupt the file, bigger isn't always better
From an almost-discharged state, the Mobius OEM capacitor requires approximately 25s of uninterrupted power before it is ready to save the file.
If power is received for under 25s (approx) before switching off, there is no file - not even a corrupt file.
 

jokiin

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Too many ¯\_(ツ)_/¯
From an almost-discharged state, the Mobius OEM capacitor requires approximately 25s of uninterrupted power before it is ready to save the file.
If power is received for under 25s (approx) before switching off, there is no file - not even a corrupt file.
put bigger capacitors and those numbers will change
 

2000rpm

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Ah... OK, I see what you mean. So, it's the "brown out" during cranking of the engine that can confuse Mobius into starting up and then being starved for power when using a capacitor before full voltage is restored. Hence, that is why the StreetGardians Cam have a startup delay. (y)

Thank for the information.

In fact that reminds me that it is for that very reason that I had implemented a DIY delay circuit in my daily driver for the 12 V rail. The transient killed the original power converter in my boost gauge.
Momentary loss of power during cranking will cause Mobius capacitor versions to shut down and not restart due to the camera being set for 'immediate' power-off-disconnect (the power interruption being shorter than the time taken for the cam to power down, therefore the signal to re-start occurs before the cam has powered down and the cam does not receive a signal to power-up after the power-down is complete).
If set for 10s power-off-disconnect in order to try to avoid the unintended shutdown, the cap doesn't hold enough power so the last file isn't saved.

JooVuu significantly improved on the quirks of the Mobius; the JooVuu charges its cap in about 15s and the cam can be set for 3s power-off-disconnect which both avoids unwanted shutdowns and retains enough power in the cap for proper file saving after power is lost and about a week of date-time retention.
 

murcod

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I've written about the problem in my car - if I leave it sitting for 4 or more days the front Mobius crashes when cranking the engine. This is related to the state of charge of the capacitor (I've ruled out vehicle battery charge by charging it fully before starting.) That one is hooked into the lighting circuit which shuts down ~ 12 minutes after locking the car. If driven within the rough four day period the Mobius auto starts fine. I've got a "delay off" timer I'm looking to install, but I want to first check what sort of standby current the circuit draws. (I don't want to introduce a new fault- the vehicle battery going flat from parasitic drain.)

The rear one is hooked into an "IGN ON" power source and doesn't have that problem (I've got a smart fob push button start ignition so the vehicle goes straight from off to engine running.)

I checked both of them this week and both had lost the date time around December 15th (last recorded file) and reset back to 1st January 2012. This wouldn't be a huge issue (for me), but if you lose the date time regularly it ends up overwriting those 1st Jan 2012 files- which you may have wanted to keep!
 

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