Looking to make a multi system cooling system that uses fans with window venting and engine systems with starting capabilities utilizing cabin and outside air sensors along with wifi capabilities for controls (thermostat setting and cooling styles) and override functions for testing and personal desire. A basic diagnostics software program so to say.
you should be able to find a daughter board offering huge numbers of opto isolated industrial purpose relays for machine control, addressable via an 8 bit value, I bet.
the onboard stuff needs to be beefed up and most arduinos lack enough pinouts presented externally.
for a 12v relay you'll want to get an external power supply to power the relay board with outgoing voltage https://www.sparkfun.com/products/15664 the arduino only has 3.3v or 5v out, so you'll use the GPIO from the arduino to tell the https://www.mouser.com/ProductDetail/Microchip-Technology/MCP23016-I-SP?qs=wJ05WdDZ4qSh1zpy%2FYO6vg%3D%3D io expander which one of the 16 relays to turn on. I'm actually building my own garden watering system... the arduino doesnt have enough pins for 16 relays, so thats what the io expander does. Basically something like 4 pins as 4 bits so you can count to 16.
It will be applied to an oe van and intend to also have a voltage guard just to be sure. The venting fans will be operating at 5 volts and so far I can run those all day long with out significant voltage drain for starting. The window open and closing function takes about nothing for that momentary action. So that's venting.. then the ac is utilizing the engine ac (very inefficient and ild like an affordable alternative but I can't think of any besides adding more cooling hoses, refrigerant, and external pump and engine that is sized to the pump, and tap into the existing system.) In that scenereo yes I would definitely need eyes on the battery as nothing operating will be also charging it.
thanks. I think your interpretation of my project is a bit off.. I'm just starting and stopping already operating automitive systems. Key functions, engine management functions, security functions... All of which just need powering up and the RFID key spoofed.
The vent is just momentarily using 12v window motor and kicking on a 12v power for the 5volt phone charger plug to run a 5 inch USB fan.
I think the other two answer are the solutions I'm looking for.. it's just been a while since I ef'ed with the stuff.
[ + ] try
[ - ] try 2 points 2.8 yearsJul 30, 2021 23:26:58 ago (+2/-0)*
the onboard stuff needs to be beefed up and most arduinos lack enough pinouts presented externally.
14 bucks : 12 relays
16 Channel 12V Relay Module Optocoupler Protection Power Supply Arduino PIC DSP
$14.20
https://www.etsy.com/listing/957039362/16-channel-12v-relay-module-optocoupler
60 bucks 16 relays :
https://www.ebay.com/itm/180870539185
you could make one with far more than 16
BUY AND TEST TWO!!!! Put the other spare in bag next to deployed. that way no downtime if a big problem a year or two later.
you can chain relays to larger relays if you need to turn on or off heavy juice stuff
[ + ] FuckYou77
[ - ] FuckYou77 [op] 0 points 2.8 yearsJul 31, 2021 11:55:19 ago (+0/-0)
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[ + ] badkangaroo
[ - ] badkangaroo 1 point 2.8 yearsJul 31, 2021 05:29:33 ago (+1/-0)
for a 12v relay you'll want to get an external power supply to power the relay board with outgoing voltage https://www.sparkfun.com/products/15664 the arduino only has 3.3v or 5v out, so you'll use the GPIO from the arduino to tell the https://www.mouser.com/ProductDetail/Microchip-Technology/MCP23016-I-SP?qs=wJ05WdDZ4qSh1zpy%2FYO6vg%3D%3D io expander which one of the 16 relays to turn on. I'm actually building my own garden watering system... the arduino doesnt have enough pins for 16 relays, so thats what the io expander does. Basically something like 4 pins as 4 bits so you can count to 16.
[ + ] FuckYou77
[ - ] FuckYou77 [op] 0 points 2.8 yearsJul 31, 2021 11:26:40 ago (+0/-0)
[ + ] FuckYou77
[ - ] FuckYou77 [op] 0 points 2.8 yearsJul 31, 2021 11:55:01 ago (+0/-0)
[ + ] ParnellsUprising
[ - ] ParnellsUprising 1 point 2.8 yearsJul 30, 2021 22:16:34 ago (+1/-0)
In theory it matters how much power spike you might want to pull at any given time.
But you can realistically do 4 with one of those to monitor temperature and flow. So 3, unless you want to unwillingly burn something down.
[ + ] FuckYou77
[ - ] FuckYou77 [op] 0 points 2.8 yearsJul 31, 2021 11:56:40 ago (+0/-0)*
The vent is just momentarily using 12v window motor and kicking on a 12v power for the 5volt phone charger plug to run a 5 inch USB fan.
I think the other two answer are the solutions I'm looking for.. it's just been a while since I ef'ed with the stuff.