Relay not working with pumps
im using a 12v battery power supply (those for drills) for testing. Heres my wiring setup:
Arduino VCC-> 12v relay VCC
arduino gnd -> relay gnd
Relay COM -> 12V+ power supply from battery
Relay NC -> Pump +
Pump - to 12V- power supply.
Code is set to LOW.
No clicking noise from the relay, lights do turn on.
46 Replies
NC stands for Normally Closed so as you described above the relays load would normally be powered, 12v into COM connected to NC
it does work in the case of a default 1 channel relay
however for my project i require 8 channels. It doesnt work in the latter case.
then you may have a power problem, an 8 channel relay needs more coil current than a single channel
5V comes from arduino
into COM is 12v from battery
so Uno 5v pin is powering the relay board
if you leave the relay outputs disconnected does the relay behave?
normally only NO or NC is used with COM... 🤷♂️
not sure what you are trying to show, the single channel unit has a power indicator
sorry lemme send the relay w pump:”
i would expect the relay LED to go on and off with the relay clicks, and the pump should run / not run with the clicks
some relays want LOW to turn on, some want HIGH
I tried setting as HIGH
the videos aren't helping me, what is the issue?
Im not sure if i’m connecting it incorrectly
I replicated the wiring the same way, the LED ligjts up but not the pump
think of the relay output as a simple switch
COM connects to NO when the relay is active
Mhm
relay off = the contact is OPEN
relay on = the contact is closed
Hypothetically it should run if i connected it the other way
and if i switch the arduino off then it wld stop running right
😭 I’m not built to be an electrical engineer
yes, COM and NC are normally closed (shorted together)
COM and NC wouldn't care if you owned an Arduino 😉
Then if i switched the output, rather the relay
then it would stop it from running
Oh yes i did see this before
COM to NC is a connection even if the relay board isn't powered
COM to NO requires the relay to be energized (relay board powered AND the correct control signal)
aight let me try
uh with both highlow signals
:”!
you can even leave the arduino out of it
connect a wire from relay ground to IN, does it click?
if not, relay 5v to IN, does it click?
as in
the relay board’s GND to the in1?
don't have the arduino pin connected for above test
Im so sorry im not super good w these
ground or Vcc, tests if relay trips with LOW or HIGH
ok i connected like
this
in1 is ground
would this be right?
you do need to power the relay board with 5v and ground
then connect an IN to one or the other
use red for 5v, black for ground, the electrons don't care but it makes it easier for humans to follow
(Vcc = 5v)
there, doesnt seem to have a clicking sound:(
connect one of the INs to 5v or ground with a jumper wire
I’m not following.
For this case I connected ground to in2.
I’m powering 5V hsing arduino.
And the power to arduino from a powerbank (temporary source:”)
only connect 5v and ground to the relay (no other connections to Uno)
connect a wire from one of the IN pins to either 5v or ground and listen for a click
No clicking noises
no LED lights up?
led lights up
no click
sry, afk, at work
if the LED lights up but no click I'd suspect you don't have enough power available to drive the relay coil
Hm..
"And the power to arduino from a powerbank (temporary source:”)" < suspicious
i stepped up the voltage using a 6009
😅
power = volts * amps, both are important
wdym "stepped up", don't go above 5v...
oh.
oops…
i figured out the issue
hehe thanku for ur helpp