Author Topic: Signal Reading  (Read 5937 times)

can

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Signal Reading
« on: August 23, 2010, 01:06:28 AM »
Hi. I have a motor driver that output TTL 4096 signal. Can I use it to calculate the number of revolution the motor has rotated?

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Re:Signal Reading
« Reply #1 on: August 23, 2010, 10:13:38 AM »
what do you mean by TTL4096 signal? TTL is digital logic voltage, which means 0 to approx 1 volt is logic 0, +2.5 to +5V is logic 1. The number 4096 suggest that it is either a 12-bit analog or PWM or frequency output. How to interface depending on what it is.

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can

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Re:Signal Reading
« Reply #2 on: September 23, 2010, 07:08:20 AM »
Hi. Actually I'm trying to determine the number of revolutions by using the A and B signal from a 5v encoder. Can 888 determine the number of revolution using the signal? Thank you

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Re:Signal Reading
« Reply #3 on: September 23, 2010, 08:37:58 AM »
You need an interface to convert the TTL signal to NPN output. A ULN2003A will do the trick. Please read the PLC's User's Manual - there is description on the wiring method there.
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can

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Re:Signal Reading
« Reply #4 on: September 28, 2010, 07:57:00 PM »
Hi. I've seen the diagram on using the UN2003A. Just want to make sure something. Do I connect the 0V from the encoder output, pin 8 and PLC 0V together even though the encoder is drawing from it's own power supply while the PLC is drawing from another power supply?

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Re:Signal Reading
« Reply #5 on: September 28, 2010, 09:53:27 PM »
Yes, if the PLC and encoder and using different power supply then you need to connect their 0V together to provide a common reference.
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