I have 18 conveyor lines that have 3 reflective photoelectric sensors each. First 2 are wired in parallel while the 3rd is by itself. The goal was to install a stack light with 3 lights (green, yellow, red). So when no eyes are blocked the green light is on. When the first 2 eye are blocked the yellow light turns on. When all 3 eyes are blocked the red light turns on. I have figured out the circuit to act in a way where no other combination of eyes being blocked will inadvertently turn on a light. i.e. 1st & 3rd eye blocked = green light ,2nd & 3rd eye blocked = green light, etc.

I initially tried the project with regular ice cubes relays but quickly found out that the lights will switch on/off every time product goes by. This was not going to work so I purchased several Finder part # 80.01 relays. I am using the on/off delay with a control signal.

I have attached the schematic I put together.

So, when the photoeye sees nothing, the control signal is 120vAC. When it is blocked, the control signal is supposed to drop to 1v or something similar (according to my bench setup). I have installed the first 6 lines successfully but the 7th, 8th, & 9th line are doing something strange. When the eye is blocked I am receiving a voltage of 7-10vAC. Apparently this is enough voltage to not allow the relay to turn off. I have tried sourcing the problem but am coming up empty handed. According to the relay specs it takes 12v min to activate so not sure why this residual voltage is causing me headaches.

Hope I was thorough enough in my explanation.
Any help with this would be appreciated!

 

Update: Just talked to Finder and they said that the voltage leak is between A1 and B1 and that I would have to install an isolation relay, which I would really like to avoid since I would be replacing those isolation relays every 6 months due to massive amounts of cycles. Also, the 12 volts min I mentioned is only for the coil. That was my mistake. Lastly, on the schematic the ground symbols technically represent neutral line not ground earth.

 

Try a two resistor divider at the output of the sensor to ground, to reduce its OFF voltage.

I don't know what control current the relay requires, so can't recommend a value.

 

Wouldn’t a voltage divider also divide the voltage when the input is 120v vs 10v?

 

Wouldn’t a voltage divider also divide the voltage when the input is 120v vs 10v?

Yes.
But you don't need the full 120V to operate the relay, correct?

 

Yes.
But you don't need the full 120V to operate the relay, correct?

Yes this is true. Apparently I only need 10v haha