openinverter forum

FJ3422 wrote: ↑Sat Aug 22, 2020 5:39 pm They are indeed very cheap compared to e.g. the Tesla DC-DC's which start in Europe on Ebay at €500.

I found some GM Service bulletins; there will probably be several part nr's around:
2016 model: 24275451 -> 24277705 -> 24283105 -> 24286781
2017-2018 model: 24281923 -> 24286781
2019 model: 24277908 -> 24296191

The one I tested is a 24284603 / MSE718B. Just saw one on Ebay USA for <$100

arber333 wrote: ↑Tue Aug 25, 2020 9:06 am I dont mean to sound too corrective, but all of the above numbers are for Chevy Volt II charger not DCDC.
24284603 is the actual DCDC converter.

arber333 wrote: ↑Tue Aug 25, 2020 3:54 pm Hm... Damien, Isaac, could Chademo (LEAF) VCU take care of 2x analog pwm signal for DCDC and volt ii charger ?

Isaac96 wrote: ↑Tue Aug 25, 2020 4:08 pm
Maybe next week. Certainly possible, but we still don't have CHAdeMO tested.
@FJ3422 has the DC/DC signals all working, if someone could do the same for the charger I'll think about adding VCU functionality.

-Isaac

arber333 wrote: ↑Tue Aug 25, 2020 4:55 pm

Isaac96 wrote: ↑Tue Aug 25, 2020 4:08 pm
Maybe next week. Certainly possible, but we still don't have CHAdeMO tested.
@FJ3422 has the DC/DC signals all working, if someone could do the same for the charger I'll think about adding VCU functionality.

-Isaac

OK, I haven't considered we could be using Chademo functionality in parallel with EVSE charging, just the VCU with alternative code.
But if we could use CAN, PWM transmit and Chademo with the same VCU that would be really awesome.

Tnx

Jack Bauer wrote: ↑Wed Aug 19, 2020 6:49 am Folks please at this point no modifications. Once we have one system proven to work everyone will be free to fork it off and make their own version.

arber333 wrote: ↑Thu Sep 17, 2020 12:43 pm @ FJ3422

Can you try giving Pin1 either 3V3 or 5V signal. I am curious if it really needs PWM control or is its input just RC filtered and used as analog voltage detection.

tnx

FJ3422 wrote: ↑Tue Dec 01, 2020 7:32 am I currently do not have a batterypack ready for testing (so no decent HV source), but will test it as soon as I have !

If you are looking for a simple PWM-source, search for "NE555 PWM board' or something similar. e.g. at Aliexpress for < 1$.

FJ3422 wrote: ↑Tue Aug 25, 2020 3:18 pm You are completely right; swapped the DC-DC & charger numbers.
Tested the Volt gen2 charger as well (check the picture of the workbench, below the DC-DC). Nice compact unit, charges at max. 3,6kW (230V 16A). Outputs ACvoltage & HVdc voltages as a 100Hz PWM signal, and limits the AC current according to a PWM signal setpoint. I don’t know if scaling of the setpoint is already known, if not I will post it here.
Drawback of the Volt Gen2 charger is that you will need an additional controller for the EVSE communication, pilot signal cannot be wired directly to the charger.

Some other chargers do have this onboard (e.g. Mitsu Outlander, can also see it on my workbench). Still looking around for an affordable BMW KLE charger to test, this is as compact as the Volt charger, and has pilot communication onboard according to the BMW wiring diagrams.

arber333 wrote: ↑Sat Mar 20, 2021 7:48 pm Did you connect 12V battery or just the load?

FJ3422 wrote: ↑Sun Mar 21, 2021 8:13 am Yes I connected a small battery on the output. That might probably be needed to let it start.
I can't remember the PWM frequency, but I used the same as on the output (which you can measure). Given the fact that the charger uses 100Hz, I guess the DCDC also takes 100Hz.

FJ3422 wrote: ↑Sun Mar 21, 2021 8:13 am Yes I connected a small battery on the output. That might probably be needed to let it start.
I can't remember the PWM frequency, but I used the same as on the output (which you can measure). Given the fact that the charger uses 100Hz, I guess the DCDC also takes 100Hz.

arber333 wrote: ↑Sat Oct 09, 2021 12:29 pm

FJ3422 wrote: ↑Sun Mar 21, 2021 8:13 am Yes I connected a small battery on the output. That might probably be needed to let it start.
I can't remember the PWM frequency, but I used the same as on the output (which you can measure). Given the fact that the charger uses 100Hz, I guess the DCDC also takes 100Hz.

Hi i have a question again. This Volt Gen2 DCDC will not stop. As soon as i provide PWM it will start at 14.2Vdc. But if i remove PWM signal it will drop to around 13.6Vdc and stay there indefinitely. While i tried to vary PWM i gave it 40% duty and it stopped. But if i would remove PWM it would revert back to 13.6Vdc.
Can you confirm that? Is anyone using this DCDC with or without contactor and had similar observation?

Pin1 = Voltage setpoint -> PWM 10...90%  
			-> >10% starts converter, default 13,80V
			-> 70-90% gives 13,80V...15,00V
Pin2 = NC
Pin3 = Status           -> 10% = In operation
			-> 70% = HV ready, no voltage setpoint
Pin4 = NC
Pin5 = +5V supply, limited at 30mA. Not used by GM
Pin6 = +5V input, internally pulled high. Not used by GM
Pin7 = NC
Pin8 = NC