I'd worry that if someone wanted to run the FB off a 5v supply, that relay wouldn't latch the coil. It would limit the user to only 12V operation, without a wider range relay.
Printable View
I'd worry that if someone wanted to run the FB off a 5v supply, that relay wouldn't latch the coil. It would limit the user to only 12V operation, without a wider range relay.
Well you can run 5v relays off of 12v, they just get hotter. So "wide range" relays, are just low voltage ones with low switch current which is what the 5v version of those relays are. Same footprint and everything so it is a drop in replacement.
We can try a board at 12v and 5v, and the 5v at 12v perhaps.
This is why I passed the buck, there were so many relays to look through on mouser and I'm not 100% on what it needs to be. How much heat are we talking about on the 5v version with 14.4 running it?
We can calculate it with the power drop making the coil a resistor. But without looking at the datasheet, it should be OK, just hot to the touch if on for long periods. But like I said, the 5v relays and the 12v relays are exactly the same on the outside so they can be swapped with no modifications made elsewhere.
Couldn't we put a resistor in there, that the end user could cut off if they were running 5-10V, and leave on if they were running 10-15V??
Could but it is unnecessary. Up to this point, I have never seen an externally powered Fusion Brain that is not powered off of 12v-15v. It would be simpler and cleaner to just stock 2 versions. 5v version and 12v version. The board itself would be identical, the relays would be 2 different parts numbers. That's the only difference. And the 5v version will work with 12v, no mods necessary. it will just be wasteful and generate more heat.
Ok! I don't know why I'm being difficult, everything I'm using is 12v !!
Depending on the connection to the relay (screw terminal?) I'd be in for a couple. This would be more for prototyping/testing that long term use.
$30x8 would be a bit expensive for my project ( I can get as many mini automotive relays as I need free, it's the packaging/organizing that sucks with those-still trying to find a connector block that takes 4-6 of the SPDT that I need, most are SPST)
The parts on there are mini screw terminals to go with the mini theme. :)
It is a 2 screw terminal block with side entry, not top down, and a barrier inbetween. Rated for 17.5A which match the relays, and it is still way more than probably 95% of the people need. Datasheet says 12awg down to 30awg will fit in the hole.