Using SRS (airbag) sensor to trigger shutdown/contactor open?

Introduction and miscellaneous that we haven't created categories for, yet
Post Reply
User avatar
rstevens81
Posts: 349
Joined: Sun Dec 22, 2019 10:36 am
Location: Bristol, UK
Has thanked: 21 times
Been thanked: 91 times

Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by rstevens81 »

Bit of open minded thinking here.... I'm thinking of adding an airbag sensor (or tapping into existing curcuit) to trigger a shutdown.

Ideally I would shutdown inverter (I am planning to initial use outlander internet (canbus)), then open contactors.

However it might be necessary (for simplicity) to sacrifice the inverter and just pop the contactors.

Has anyone done similar or has any thoughts?
Rule 1 of EV Club is don't buy a rust bucket....
Which rule does everyone forget 🤪
golfdubcrazy
Posts: 75
Joined: Thu Jan 28, 2021 6:15 pm
Has thanked: 1 time
Been thanked: 5 times

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by golfdubcrazy »

Does your existing vehicle have an airbag module or is it something you want to add ?

if your adding you could use the old style inerita switch which would be alot cheaper and faster with alot less problem solving.

https://www.ebay.co.uk/itm/254172211379

like the link above.
User avatar
rstevens81
Posts: 349
Joined: Sun Dec 22, 2019 10:36 am
Location: Bristol, UK
Has thanked: 21 times
Been thanked: 91 times

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by rstevens81 »

Think you are right a couple of interia switches are the way to go for the crash case .... Found even cheaper 🤩
https://www.ebay.co.uk/itm/Ignition-Ele ... 635-2958-0
Rule 1 of EV Club is don't buy a rust bucket....
Which rule does everyone forget 🤪
golfdubcrazy
Posts: 75
Joined: Thu Jan 28, 2021 6:15 pm
Has thanked: 1 time
Been thanked: 5 times

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by golfdubcrazy »

I think one is enough, anymore and you could find yourself running around the car everytime you go over a speed bump :lol: especially london speed bumps
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by arber333 »

rstevens81 wrote: Wed Dec 15, 2021 12:48 pm Think you are right a couple of interia switches are the way to go for the crash case .... Found even cheaper 🤩
https://www.ebay.co.uk/itm/Ignition-Ele ... 635-2958-0
I see that inertia switch is quite professional application. I also use those to trigger PWM stop.

Problem with SRS is how to connect to it. If you bring in a signal from the outside you could cause SRS to behave in a wrong way.
Unless your SRS computer has free ports to connect to i dont see a good way with it.

You could also use a pretensioned string which would be touching a GND contact and providing path for a failsafe relay. Whenever the car would be deformed relay would drop 12V.
johnspark
Posts: 264
Joined: Fri Apr 12, 2019 10:42 pm
Location: Adelaide, South Australia
Has thanked: 59 times
Been thanked: 48 times

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by johnspark »

I would not dare touch the SSR circuit (Insurance issues etc...). Much better to use your own independent solution.
User avatar
johu
Site Admin
Posts: 5684
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by johu »

arber333 wrote: Fri Dec 17, 2021 12:39 pm You could also use a pretensioned string which would be touching a GND contact and providing path for a failsafe relay. Whenever the car would be deformed relay would drop 12V.
Beware of false positives. I'd rather have has little circuitry as possible that can shut down the car
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
ZooKeeper
Posts: 507
Joined: Mon Mar 30, 2020 10:23 pm
Location: USA

Re: Using SRS (airbag) sensor to trigger shutdown/contactor open?

Post by ZooKeeper »

May not apply to all, but the SRS training I have had suggests that at least *some* of the crash sensors are "single use" and must be replaced once tripped. This potentially a very big problem as if you cannot reset it, you are stuck.

The inertia switches common on the 80s and 90s vehicles were re-settable, so a better option, IMO.
Huebner VCU controlling a Gen2 Prius Inverter powering an MGR
"Talent is equally distributed but opportunity is not." - Leila Janah
Post Reply