Mobius Super Capacitor.

[cobrax3]

hey guys
i am trying to install a home-made supercap. i have 2x22F capacitors, connected to the battery port in series so that should give me 11F.
but nothing happens, they don't charge, the camera shuts down instantly when no power, and i lose the last recording. checked the capacitors, seem fine. usb charging is checked. wires are ok. i've placed the capacitors in some other place, abot 1m away.
the + is the red wire at the battery, right?
any ideas what is wrong?
thanks

 

[jokiin]

what is the exact spec on the caps?

 

[cobrax3]

thanks for the quick reply. i tried troubleshooting it. i think the capacity is too much for the mobius
they are 22F/2,7v each
keeping a voltmeter while powered on, the voltage starts at 0.30V and goes up by 0,01V each 5 sec. so it will be full in... around 2000 sec if i did correctly the math, considering 4v final tension.
wow
is there a way to increase the charging current?

 

[jokiin]

the caps are way too big, will take too long to charge, 2.7v 5F x 2 would be plenty

 

[cobrax3]

yeah i guess i did an overkill. thought to have them keep the time and save for a longer time
but if they get charged eventually, won't that mean that they will stay charged afterwards for longer? and each time i apply power to the mobius they will only have to "top up"? this "top up" will/could be only the equivalent of those 5F. the mobius won't consume more power on shutdown than it would with a 5F capacitor, right?
is there a way to increase the charging current?
is there a downside of having this much capacity? i mean for the camera
thanks

 

[jokiin]

I think they are too big regardless, better to get the right size for the job

 

[Deleted member 46308]

I think they are too big regardless, better to get the right size for the job

That has been suggested in my life on a couple of occasions

 

[cobrax3]

lol. bigger should be better in this case. ill try and see what happens after its filled

 

[Padwanjoe]

Hi. There are almost 10 months since I put the supercapacitor and my rear mounted Mobius B Lens started and recorded every single time I started the car engine.
Here we had two weeks when the night temperature was from -7 to -15 Celsius and the Mobius remained in the car and started recording in the morning.
Off-topic: my Shadow GT680 and my JooVuu X Beta 2 Unit were recording fine in the same weather conditions, but they were alternatively used as my front dash cam.

 

[mr_milo]

hey guys
i am trying to install a home-made supercap. i have 2x22F capacitors, connected to the battery port in series so that should give me 11F.
but nothing happens, they don't charge, the camera shuts down instantly when no power, and i lose the last recording. checked the capacitors, seem fine. usb charging is checked. wires are ok. i've placed the capacitors in some other place, abot 1m away.
the + is the red wire at the battery, right?
any ideas what is wrong?
thanks

As others have mentioned, they may be too big however I think the issue is more likely that they have too much resistance. Look at the ESR of the caps and I bet it's up there. For reference, the supercaps I used on my Mini 0803 had an ESR between 30-80mOhms. Anything much more would take forever to change with 22uF, even 80mOhms might be too much with that much capacitance.

 

[cobrax3]

http://www.tme.eu/en/Document/949d27499e9d08025574b98f3f5b24c1/edlc.pdf
this is the capacitor. scroll to second page
Samxon DRL226S0TK25RR
it says < 0.050 ohm at 1khz
tried again today on my way home. i think it charged exactly when i predicted, 30-40 mins. the camera was recording, yellow led flashing. then for a while the yellow led started flashing intermitently with the green one. it was yellow-green-yellow- etc. i was scared something happened, but i think it was telling me that the battery/capacitor is full? after a while (don't know how much time, maybe 1-2-3 mins (i was driving) it went back to just yellow flashing and it continued recording. am i correct? that's what was happening?
thanks

 

[mr_milo]

http://www.tme.eu/en/Document/949d27499e9d08025574b98f3f5b24c1/edlc.pdf
this is the capacitor. scroll to second page
Samxon DRL226S0TK25RR
it says < 0.050 ohm at 1khz

I couldn't find the DRL226SOTK25RR in the datasheet but did see the DRL226MOTK30RR which is <0.050 ohms. With the two in series your ESR, if my calculations are correct, would be ~0.1 ohms.

My Mini 0803 setup is as follows:
Internally I have two 6F 2.7V Super Caps, Eaton Bussmann P/N: HV0830-2R7605-R, in series, which are in parallel to another two 3F 2.7V Super Caps, Eaton Bussmann P/N: HV0820-2R7305-R, in series. These internal capacitors are in parallel to a 3F 5.4V Super Capacitor, Eaton Bussmann P/N: PHV-5R4V305-R, which is mounted externally. Basically I started with what I *thought* would work but just had to keep adding on. It looks like that might have helped reduce the ESR but I'm not sure .

The first two 6F caps end up giving me 3F @ 5.4V with 0.080 ohms ESR. The second two 3F caps provide 1.5F @ 5.4V with ~0.160 ohms ESR. The last 3F, 5.4V cap has ~0.080 ohms ESR so with all of them in parallel I get a total of ~7.5Fs @5.4V with ~0.32 ohms ESR. This setup still takes several second to a minute to charge up.

 

[jokiin]

Basically I started with what I *thought* would work but just had to keep adding on.

the challenge for you is you're using a product that was only ever designed with a battery in mind so hardware design and firmware are not correct for the application

 

[cobrax3]

looks like everything worked this morning too. so once it is full, all is well
i only need to know what that green-yellow-green-yellow means. this morning it did it again, for about 1 minute

 

[mr_milo]

the challenge for you is you're using a product that was only ever designed with a battery in mind so hardware design and firmware are not correct for the application

Agreed, however I was just posting that info for reference to the ESR of the caps and the caps which I used. My setup has been working fine for well over a year now. My only issue is if I start the car and don't run it for at least a minute. Those unintentional starts of the ignition circuit kill the camera every time. The good news with the mini, is that after a few minutes the GPS updated the time & date so I don't have to.

 

[mr_milo]

looks like everything worked this morning too. so once it is full, all is well
i only need to know what that green-yellow-green-yellow means. this morning it did it again, for about 1 minute

Unless you totally discharge the cap, they will only need to charge the amount they discharged during shutdown. So unless you leave it for a long vacation you should be good, but still overkill.

 

[russ331]

Update. I installed capacitors in my two Mobius cams exactly 2 years & 1 year 9 months ago, respectively. Both cams start recording when the engine is started. Both hold date & time correctly, & save the last file after the engine is switched off.

 

[kevster]

I have recently changed from battery to a super capacitor and I now get interference that wasn't there running on battery.

I fitted one of these

https://www.joovuu.com/gb/other/95-mobius-super-capacitor-.html

 

[mr_milo]

That doesn't seem right, unless the foil of the battery was acting as a shield which is highly unlikely since it would just go around it.

Have you tried reinstalling the battery to see if the interference goes away? That would be my first step.

 

[kevster]

That doesn't seem right, unless the foil of the battery was acting as a shield which is highly unlikely since it would just go around it.

Have you tried reinstalling the battery to see if the interference goes away? That would be my first step.

Thanks for your reply. That was my thought too. What I can hear is a faint electrical pulsing.

It doesn't over bother me but as I say wasn't there before.