Hello there, i'm going to create a remote launch for a car that i'm modding and need your input on the topic of safeguarding.
From the experience i noticed the mosfet modules not so safe to handle a crucial relay itself. so i'm going to chain some relays like NO-NC-NO-NO and use trigger those combinations programmatically the the action.
is it overkill for a such device security or can you suggest simpler methods to prevent accidental triggering on this kind of devices?
Like all solid state electronics, MOSFETs are super-reliable as long as you use the "right" one in the right circuit. Or a regular bipolar transistor may be better for a relay driver because transistors are turned fully-on by a lower voltage and relay coils don't require a lot of current.
The MOSFET or transistor should outlast the relay. (Although a relay can last many years if not stressed.)
Or, solid state relays don't (usually) need a driver and they can "last forever" if they are not over-stressed, but AC & DC SSRs are not interchangeable.
I would suggest you first do some research and learn what automotive electronics is. It is one of the nastiest environments you can put electronics in. Your modules can see for example load dumps that have tons of amps behind them with an amplitude of maybe 80V +- depending on the make and model of car.
okay, the term "automotive" is confusing. this is a general idea, let's say i'm building a nuclear bomb and creating a remote trigger for it. how i can make sure it won't explode by accident without my command?
my current idea is using chain of relays as an XOR gate, circuit will be close after a 4 bit parallel command and also those relays will be protected by capacitors that only trigger only after 500ms of voltage.
let's do some brainstorming, what would be the another idea?