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Topic: Can Arduino Deuminalove provide enough power (Read 1 time) previous topic - next topic

AeroBoy

Hi,

Im using a Arduino Deuminalove board with XBees to provide motor commands to 3 4.5 v motors

The motors will have reverse and forward motion commands through PWM signals.

My configuration is as follows:

2 FSS1-102Z DC 5 2A 250VAC solid state relay for each DC motor.
(2 positive PWM signals provided from the PWM pin outputs from Arduino)

I am using a 7.V lipo battery to provide power to my board.

i'm using the 5V onboard power to provide power to all 3 DC motors by shorting all relay load(power) ends together in a breadboard.

Is this a safe method to draw power from Arduino or should i just use a 7.4v External power source to power my DC motors alone?

please advise.

PaulS

You have an AC relay switching DC power? That's not a good idea.

What is the PWM (rapid switching of power on and off) actually controlling? Not the relay, I hope.

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I'm using the 5V onboard power to provide power to all 3 DC motors by shorting all relay load(power) ends together in a breadboard.

What, exactly, are the relays doing?

The Arduino will not provide enough power to power 3 DC motors, unless they are incredibly tiny. Even most of the tiny, no-power motors draw too much current.

Post a sketch of how you have stuff wired up.

AeroBoy

The board has a max output current of 40mA.
The DC motor each needs at least 2A of current for them to spin

So i used the relay(Which worked with 1 DC motor) to 'step up' the current to spin the motors

Now i need to spin 3 motors. Each motor is running at 4.5V 2A. I am connecting each ends of a DC motor to a relay and the relay is connected respectively to a load and PWM signal.



Thats the link for my sketch. If u cant view it.Please provide me your email and ill send it over. Thanks for the help

Grumpy_Mike

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I am connecting each ends of a DC motor to a relay and the relay is connected respectively to a load and PWM signal.


WTF!!!
You can't connect a PWM pin to a relay and expect to do any good. You can't power a relay coil direct from an arduino, you need a transistor. You also need a diode across the relay coil.

AeroBoy

I know wat u mean,

Ive tested with 1 dc motor and a relay connected with the arduino and it worked perfectly (one direction) i didnt see any faults with the connections either.


Grumpy_Mike

#5
Oct 13, 2010, 03:48 pm Last Edit: Oct 13, 2010, 03:50 pm by Grumpy_Mike Reason: 1
Quote

Ive tested with 1 dc motor and a relay connected with the arduino

So with a relay connected directly to an arduino?

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and it worked perfectly

What sort of this was this? Was it just a functional test or a parametric test. If you have connected a relay coil direct to your arduino you have almost certainly damaged it. It might still function but probably not for long. Do you know the current the coil is pulling? Anything 40mA or over has damaged it.

Also why are you posting a hardware question here. look at the top of the page and it clearly states:-
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Using Arduino with other software (Processing, Flash, PD, MaxMSP, etc.)

This section is NOT for the software problems you get when interfacing hardware!

AeroBoy

Oh yea. I forgot abt that. Thanks for the reminder and ur time Grumpy Mike.


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