Smart Camera Input reads low

[BruceAmmons · Accepted solution]

How do you have everything wired?  The inputs and outputs are isolated, so you need to connect both the + and - connections to a complete circuit.  The power and ground connections to the camera are not connected to the outputs.

For the inputs, you can test them by connecting 24V to the ISO IN + and ground to the ISO IN -.  The input should turn on when you connect the 24V and turn off when you remove it.

For the outputs, you could wire 24 V to one end of a large resistor, and connect the other end of the resistor to ISO OUT +.  Connect ground to ISO OUT -.  When you turn on the output, the voltage across the resistor will be 24V.  When the output is off, it will be 0V across the resistor (24V on both ends).

Bruce

[jblc]

Check out the above posts in this thread where the wiring is explained in detail.  I have it setup as you describe.  But, the camera's data monitor is not reading the input signals.  Is there something that needs to be enabled?

[BruceAmmons]

Actually, the way you have it wired up is not clear at all.  You talk about wiring the 24V to the + inputs, but you don't say if you connected ground to the - inputs.  No explanation at all about how you wired the outputs.

Bruce

[jblc]

  You are right about the grounds!  Thanks for being persistent in your reply.  Yes, the ground on the inputs were separated, and only were connected at one point through scope grounds; that's why it worked before temporarily.

  Once the scope was removed, it no longer worked.  The I/O now works properly.  Thanks Bruce!

[BruceAmmons]

Yeah, isolated inputs can be confusing because they work differently than regular ones.  You have to connect both ends properly for them to work.

By the way, my original answer was correct.  You had it wired up wrong.  I figured one of the two answers had to be correct.

Bruce

[jblc]

Yes, your original answer was correct, that's what I used as a reference to find the error.  I've marked that answer as correct.  Thanks again.