Arduino + Relay(220V) Problem.. Need Help!

[viel]

Thank you Chris.

I don't have oscilloscope, its just for school project. and i think I'm messing up in here. i already tried to externally supply the arduino via 5v 1amp usb charger.

is there another/improvise way to check things out here?

im trying to upload a video, but my internet is slow.
im resoldering the Capacitor.

 

[davenn]

How to put a zener diode across the transistor?

I don't understand what he was getting at either ??????

do you mean i should change my diode to zener across the relay?

No, that should be a standard 1N4004 (any in the 1N4001-4007 series) diode

 

[cjdelphi]

It was 3am about to fall asleep..

The diode which acts as a flyback (negative voltage spike) to ground, so the transistor is not damaged

In my head i was just thinking of ways to supress the voltage spike, a zener might be any good but it will supress higher voltages being induced back into your circuit

If not for this really bad back pain which came on this morning, i'd build it myself

 

[CDRIVE]

Hi, I'm working on a project using arduino and relay to control a 220v with LCD Display.

My Components are:
A.) Arduino with Wifi Shield going to:
B.) Serial to parallel decoder (Shift Register 74595) two of them in series to Control:
a.) 2x16 LCD.
b.) Relay(10A 250vAC) with Current Sensor (ACS712)

View attachment 25423

Everything works fine without load, but when i load a 220v (Electric Fan) my Arduino Restarts.
Please Help me. i thought my circuit is just fine..

Any Help is Appreciated...

OK, grabbing at straws here so here's a couple of thoughts.
I see a 220VAC receptacle on your print but I don't see where it connects to the Mains.

Since we are shooting blind here can you please disconnect the output pin of the ACS712. Then ground the Analog input of the Arduino and report if the Arduino still resets?

Chris

 

[CDRIVE]

This is just supplemental to my last post regarding the ASC712.

I've never used or spiced this chip but I just finished reading through the Datasheet. As per the Datasheet the Vout(Quiescent)= Vcc * .5 or rephrased.. Vout(Quiescent)= Vcc/2. When the input current (Iin) goes more positive Vout goes more positive. When the input current (Iin) goes more negative Vout goes more negative. So if you're monitoring Mains AC current Vout is going to be a sinewave that floats above zero. Because when zero crossing occurs Vout = +2.5V.

Why am I mentioning this? I have no idea. Assuming you already know this should I assume that your Arduino ADC code does also?

Moving forward, here's a question that hasn't been asked. Is your Arduino Reset pin pulled up to +5V through a pullup resistor?

BTW, I'm assuming that this entire project boils down to an LCD Ammeter. Is it or something else. Also what does your 220VAC fan pull?
Since it's an inductive load it's likely throwing a spark at the relay contacts when they close or open. If so you may need an AC Snubber across the contacts.

Chris

 

[Bluejets]

Just wondering what the usb lead is doing in the photo.
Are you trying to monitor something while powering from the transformer?
Do you realise you cannot power from 2 sources?

 

[CDRIVE]

I have a sinking feeling that his project was due today. That's unfortunate. I'm sure all of us wanted to help him and see it turned in on time. The young man's photos indicate that he does neat work too!
I hope he comes back.

Chris