How to connect a 24 volts PLC output to L298N motor driver pins IN1 made for arduino using a buck converter

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Hi,I'm using a plc SR3B261BD, that has a 24 volts output, and a L298N motor driver that works at 5volts, I'm using two 24 volts dc motors , that's why I connected a 24 Volts power source (and removed the jumper), and a 5 volts power source to give power to the driver. My main problem is that IN1 works at 5 volts and plc works at 24volts, that's why I'm using a buck converter, but I don't know where to connect the OUT- (negative output ) of the buck converter, should I just connect it to L298N ground?
I've even thought of using a resistor to reduce the output voltage of plc but I can't find any information about the output current so I can't calculate the value of the resistance.

ard
ard1391×663 112 KB

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Did a voltage divider using two series connected resistors NOT work for you?

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Thank you for answering, I didn't apply that solution yet, because I don't know how to chose the right resistance value, at what values should I look?

ard
ard1391×663 69.7 KB

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As stated, a voltage divider it TWO! resistors in series and will be connected on one end to the PLC + output and the other end to the ground. I understand there are even web sites that will calculate the resistance values needed.

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Like this? But how to I take in count overheating of the resistor?

ard
ard1391×663 81.7 KB

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NO overheating! Only 3-4 m will go through the resistors.

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What 3-4 means :thinking:

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Sorry. typing is bad. 3-4 ma, milliampers!

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Are the 24V signals analog or digital?

If digital then you can block 24V from 5V with a diode and a pin INPUT_PULLUP on the 5V side. When the 24V side is LOW 0V the pullup 5V will drain through to the LOW and the 5V side reads a LOW. When the 24V side is HIGH the diode doesn't drain the pullup, 5V input reads HIGH. It does need a diode per 24V--->5V channel.

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Oh thank you, so you confirm that the wire connection is in fact correct? Or do I need to do something else

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Thank you for answering,yes they are in fact digital, but at home I have some resistors so I think it would be faster that way. In the future I will surely try that solution too

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You could probably use a components grab bag from a hobby electronics store! I remember finding compartmented trays with lids at harbor Freight! I started buying assortments to fill out my options.

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How were your connections finally?
I just had the same problem as you. Could you help me?

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