Comments on: Check Electric System message

By: Jeroen Meijer

Jeroen Meijer — Fri, 10 Feb 2017 12:19:45 +0000

In reply to Borut. Please log as request on the bug tracker. Indicate if the field you would like to see is the same as 12 volt system current in the charging tech screen

By: Borut

Borut — Thu, 09 Feb 2017 16:23:16 +0000

Hi
Can you make 12 volt consumption graph with total consumed energy on 12 V bus.
The phone should be connected all the time for logging.

By: Tobias

Tobias — Thu, 09 Feb 2017 08:53:06 +0000

Think there is a third reason for a failing 12 volt system:
If the DC/DC converter fails recharging the 12 battery from the traction battery during driving.
With a broken DC/DC converter even a healthy 12 volt battery will loose its capacity quite fast during normal operation, especially in cold conditions.

By: Borut

Borut — Mon, 06 Feb 2017 14:53:19 +0000

I’m looking at this battery
http://eauto.si/metron-shop/?product=lifepo4-cell-module
It is reasonably priced, can be rearrange so it will fit and it will outlast the car.
I’m not sure how often the car charges the battery at 14.3, it should on every charge cycle for this to work.
I could easy get out of the battery more then 1 kwh on a cycle where a lot of 12 V power is needed if it is possible to set the running voltage of dc/dc to a lower state . Not to low so a small charge will stay in the battery for sleep power.

By: Jeroen Meijer

Jeroen Meijer — Mon, 06 Feb 2017 14:38:06 +0000

In reply to Borut. The documentation I have seen contains very little writable items. I have a clone CLIP system on order which I hope will arrive in a few weeks, so I can have a peek, but I am not hopeful. BTW, what I wrote earlier about capacity reflected on the startup sequence of the car. In operation there can be massive loads on the 12 volt bus. Read windshield heater is fused on 40A. Same on the fan for the battery.

By: Borut

Borut — Mon, 06 Feb 2017 08:36:59 +0000

I’m thinking on replacing the leadacid with Lifepo4 4s.
The charging voltage in my car is 14.3 and that is a little under max charging voltage for lifepo4.
That would work fine.
But further I’m thinking to reduce the running voltage of a dc/dc converter to something like 12.0V.That would fully discharge the lifepo4 between charges,that way I would gain additional range.
What do you think? Do you think it is possible to modify or “correct” dc/dc converter running voltage with Clip diagnostic tool?

By: Jeroen Meijer

Jeroen Meijer — Sun, 05 Feb 2017 22:19:23 +0000

In reply to Borut.

I don’t really know. In rest (i.e. while charging) the 12 volt system draws roughly 2.5 amps, but coming from no 12 volt at all, I noticed it started clicking relays, opening the (stuck) charger plug, doing lots of startup stuff. It is a totally wild guess, but I would not be surprised is was 10-20 amps. It would also prime the brake servo pump. My wild guess is a 30C peak discharge Lipo would surely do the job, assuming the DCDC converter can take over pretty fast. Also, I would be slighly scared, because that DCDC converter can put out a lot of current, about 100 amps. If it decides to start charging with the Lipo still connected…….

By: Borut

Borut — Sun, 05 Feb 2017 19:34:36 +0000

How big of a drain it is, while initializing,would a 3s RC Lipo do the job, lets say 2200mAh,30C ?
A small weight to save your self in a situation like that.