Go Down

Topic: [Solved] I Need To Improve Power Quality (Read 716 times) previous topic - next topic


Floodlight:  1.7 Amp
You can't power that one from the V-in pin with the supply connected to the DC socket.
As explained, there is a 1Amp (absolute max) diode between DC socket and V-in.
The diode will burn out sooner or later.
Power the horn directly from the supply (e.g. splice the cable going to the DC socket).

Do you switch the horn with a relay or mosfet.
Does the horn have a diode across.

Still waiting on that full diagram, and pictures.


3 Requested photos attached

Coding Badly

Sep 13, 2017, 04:32 am Last Edit: Sep 13, 2017, 04:33 am by Coding Badly
I will enter a new post in the General Electronics forum.
The next time you feel the urge to cross-post resist that urge.

See reply #7 for what you should have done.



Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

What are the specs of your plug pack, can you post a picture of its name plate please?

Thanks.. Tom... :)
Everything runs on smoke, let the smoke out, it stops running....


Based upon the information I received from this forum, I have removed the connection to the Vin pin of the Uno.  Instead, the power supply to the alarm devices will be from a second, separate 12v brick transformer, connected to a 110 V-AC outlet.  The second power supply will have a 3 amp rating.

The Uno will continue to be powered by a 12v, 2A brick transformer connect to a 110 VAC outlet.

The alarm devices will be controlled by the Uno via a 5v, 1-channel relay.

I haven't made the changes yet since I am awaiting delivery of parts.

A schematic of the circuitry is attached.

With regards to cross-posting.  Since I believe that my problem is connected with noisy power, I made my original post to the forum that had the word, "power" in its title.  It was not until I began to receive replies that I realized I was appealing to the wrong audience in that forum.  I looked all over the web page for a link that would transfer the posting to the correct forum, but could find no such link.  Then I looked for a link that would enable me to close the issue.  Again, no link was to be found.  So, as a last resort, I posted my intentions in a reply.


Rather than wait a week for the new power adapter, I decided to test the system with the alarm light and horn removed, and by just observing the operation of the relay.  With no lead connected to the Vin pin of the Uno, the system appeared to work perfectly.

So, as suggested, the problem appears to have been caused by overloading the Vin.

Unless something else happens, at this time I believe the problem is solved and will make the appropriate notation in my original post.

Thanks, all, for your help.

Go Up