triggering 24v contactor with arduino

Projects General Guidance
1

Hi, I really hope that this hasnt been asked, but I couldnt find the specific answer anywhere.

Im going to be making a type of transfer switch using the Arduino Leonardo to trigger a 24V contactor. I cant find any 5V or 12v ones with my time limmit given. I would like to know if the 5v from the arduino would be sufficient to trigger the coil. I will be using a transister amplifier, and I really dont want another power source (24V) to connect the collector of the transistor to.

In other words: base connected to arduino output pin via a resistor. Collector connected to 5v rail (arduino) via the contactor coil. Base connected to gnd.

The contactor will be either one of the following two:
http://docs-europe.electrocomponents.com/webdocs/13ea/0900766b813eae42.pdf
http://docs-europe.electrocomponents.com/webdocs/13d5/0900766b813d52a1.pdf

Thanks

2

wahste:
I would like to know if the 5v from the arduino would be sufficient to trigger the coil.

Since thy list the minimum DC input voltage as 24V it is highly unlikely that an 5V input would do the trick.

3

So Im guessing the easiest sollution is to have a 24V supply, and just power the arduino through a voltage regulator. Then connect the collector to the 24V supply?

4

How where you planning to power the Arduino?

Use the 24v for the contactor only or your Arduino may overheat.

Use a transistor to switch the contactor and do not forget the reverse connected diode across the coil.

Weedpharma

5

weedpharma:
How where you planning to power the Arduino?

Use the 24v for the contactor only or your Arduino may overheat.

I would like a single power supply only.

6

The rated input for the Arduino will handle this voltage but only at a very low current. Is there anything else being run from the Arduino?

The power dissipated by the onboard regulator is voltage drop x current. With a 24v input, you are dropping 19V and a lot of power.

Weedpharma

7

Hi,
Forget about 24V input to the arduino, the filter caps on my clone UNO are 25V, plus I would doubt if the on board regulator is rated for 24V input.

Tom... :slight_smile:

8

Have you considered using the Ruggeduino-SE controller? Supposedly can handle up to 30 volts input power.

9

Hello

Use 24 V power supply,for Arduino buck converter and Mosfet for contactor,find examplles on You Tube.

gzajec