IP Camera I/O

I have an IP camera, Amcrest IP8M-2493E, that has some digital I/O capability. It has 3 wires:
Alarm_IN1
Alarm_OUT1
Alarm_GND

I would like to integrate this I/O to a PLC. If I short the IN1 and GND, via relay contacts from my PLC, I get a signal to the camera and it does what I intend.

However, I can't figure out how to tie the camera output to a PLC input.

The camera Alarm interface is described in the manual as "1 channel In: 5mA 5VDC 1 channel Out: 300mA 12VDC". This seems to conflict with a sketch shown in a video (https://youtu.be/I7pGznSbsBs at the 1:51 mark) that shows +3.3V power and a 5V/5mA max. output capacity.

I've tried the 10k resistor in a pull up configuration with both 12VDC and 5VDC power. Should I be using a 3.3 volt power supply? With either 12VDC or 5VDC power, I get 12VDC or 5VDC between OUT1 and GND when the output is what I would call "OFF" and 0VDC when the output is what I would call "ON".

Great, the output voltage seems to be working. However when I attach either a 12VDC or 5VDC relay to the output, the relay does not change state and the voltage drops to some low amount.

Amcrest support is almost non-existent. What am I doing wrong? How do I interface this camera output to a signal level that I can do something with?

TIA.

sounds like the ouput isnt powerful enough to drive your relay coil

Looks like the video and documentation are contradictory.

I think the video is correct and it is a sinking output which matches your operation description.

I get 12VDC or 5VDC between OUT1 and GND when the output is what I would call "OFF" and 0VDC when the output is what I would call "ON".

Click to expand...

The output will be 0VDC when on.
The output will be the supplied VDC when off.
The logic is reversed for this type of output.

You could use the output to switch an interposing optocoupler relay, which then drives the plc input.

If the plc input switches states at 12VDC you may be able to wire it directly to the input without the relay.

Here is an opto-coupler in a DIN rail package. The switching speed is a lot quicker than you need, but it is also OK at lower speeds.:
https://www.phoenixcontact.com/en-gb/products/solid-state-relay-module-dek-oe-5dc-24dc100khz-2964270

I got a 5VDC solid state relay very much like the Phoenix Contact part mentioned, wired it up per the diagram above and seems to work perfectly.

Thanks for the info.!

johnd_125 said:

I got a 5VDC solid state relay very much like the Phoenix Contact part mentioned, wired it up per the diagram above and seems to work perfectly.

Thanks for the info.!

Click to expand...

just make sure that the input current draw of the relay is below the 5ma max of the camera

It pulls about 3 mA for a brief instant which I guess would be the inrush and then goes to a very low current after that. Thanks.