DIY Electric Car Forums banner
Cancel

Urgent help needed for AEM VCU200

1159 Views 7 Replies 4 Participants Last post by  thula_mike, 
engi-goose
Hello all,
I am the electrical lead for a university Formula SAE team, and to spare you all the long story, we made the questionable decision of switching to the AEM VCU200 for our car this year because we didn't have the time to develop a custom VCU this year, and we were in the market for something that would be "plug and play" with our Cascadia Inverter and Orion BMS2. Now we find ourselves in an odd situation and long story short, we need to confirm that we can run our motor using this thing this weekend (in the next day or 2), and we are realizing the VCU200 is either super poorly documented, or there's some documentation that we never received when we purchased it. Currently we have our LV wiring harness, VCU and inverter (LV Only for now) laid out on a test bench and what we need to figure out is whether or not it the VCU is properly communicating with our inverter and then BMS. We can't actually find any way in the AEMCal software to check this and find ourselves at a bit of a pickle. The "Comms Monitor" only shows messages on CAN 1 but the inverter and BMS are on CAN 2 and 3 respectively as per AEM documentation. We are currently considering wiring everything up, HV included to see if it just happens to magically work, but that seems a little risky and I'm hoping there is a way to verify coms before we plug in HV.

If anyone here has gotten the VCU200 and could spare us some of their time this weekend, please let me know. AEM Support has kinda stopped answering our emails......
Reply
Save
Like
1 - 8 of 8 Posts
R
Prayer and magic don't work in engineering.

Ask your peers on the FSAE Reddit sub for the documentation if someone here doesn't provide it.

You're going to fry yourself out of the racing season, maybe injure someone, if you wire things up by making assumptions.
Reply
Save
Like
engi-goose
remy_martian said:
Prayer and magic don't work in engineering.

Ask your peers on the FSAE Reddit sub for the documentation if someone here doesn't provide it.

You're going to fry yourself out of the racing season, maybe injure someone, if you wire things up by making assumptions.
Click to expand...
We have reached out on reddit as well, but it's not a very popular solution, so not many people are available to help.

We aren't new to high voltage electrical, I guess I made it seem a like we where just gonna haphazardly plug things in, but rest assured that we are pretty confident our LV system is working as intended and the correct safety measures are in place on the high-voltage side. It's really only comms between the VCU we have left, and as per FSAE rules, our VCU doesn't actually control the HV disconnect relays anyways so it's impossible for a wrong settings or wrong wire on the VCU side to cause the HV contactors to close haphazardly.

Anyways we have made some progress and we think the CAN Communications between VCU200 and our BMS and Inverter are functional, now it's a matter configuring the thing correctly.
Reply
Save
Like
  • Like
Reactions: 1
R
Feel free to set up a build thread here.
Reply
Save
Like
engi-goose
Minor update if anyone knows, we can't seem to get our changes to persist. Like we will change settings, save, click on "send current calibration", it will upload successfully, however after a power cycle, the settings seem to revert, and I'm not quite sure why. Any guidance would be appreciated.
Reply
Save
Like
S
Which VCU pins are you removing power from when you power cycle?

There are separate pins for ignition and permanent 12V power. FSAE rules may have a problem with permanent power provided to the VCU, but I’d check to make sure the VCU is being powered down properly in the correct sequence.
Reply
Save
Like
engi-goose
ScottV said:
Which VCU pins are you removing power from when you power cycle?

There are separate pins for ignition and permanent 12V power. FSAE rules may have a problem with permanent power provided to the VCU, but I’d check to make sure the VCU is being powered down properly in the correct sequence.
Click to expand...
Yeah I was informed about having to turn off the wake switch individually first before doing a full power-down for it to save. This fixed the problem initially when the VCU isn't connected to anything, however it stopped working once the VCU was connected to the inverter and BMS, and turning off wake power still left the VCU on for some reason.

Another issue we have encountered since that last post is getting stuck in OP state 4, even when the safety flag is set to 1 (which should indicate all the safety requirements for getting to OP state5 have been reached. I'm not sure if anyone else has experienced this.
Reply
Save
Like
thula_mike
Hi engi-goose,

I use the AEM 200 in two of our prototypes and have had a fair bit of experience. If you want to reach out and have a call just ping me your details and I'll call you back Contact us
Reply
Save
Like
  • Like
Reactions: 1
1 - 8 of 8 Posts
DIY Electric Car Forums
A forum community dedicated to DIY electric car owners and enthusiasts. Come join the discussion about electric vehicle conversions, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
All EV Conversions and Builds Batteries and Charging Technical Discussion New Member Introductions eBay EV-Related Auctions
Top