Proximity sensor circuit

[DAlgie]

Hello, new to this forum, bit of a novice in this field. I have a metal sensing proximity sensor that I would like to use to switch an air solenoid for an autoclave door seal safety device. I assume that I will need to interface this sensor to some kind of SSR to step the signal up to actually switch the solenoid, which is about one amp. The prox sensor is a 12- 24VDC. I am not good at reading circuit diagrams, a description would be possibly better for me to get a grasp on the details if possible. I can provide more details but need to know what is wanted. Thank you to all in advance!
DaveA.

 

[HarveyH42]

Do you have a data sheet for the sensor? I imagine there are hundreds on the market to choose from, kind of tough to decide what to do with it. 12-24vdc supply, might get lucky and it already contains the driver for a relay, 1 amp isn't too bad, might handle the solenoid as well.

 

[DAlgie]

I have a data sheet, I bought the sensor new from Automation Direct. It's a NPN type, normally open, 10-30 VDC 200 MA max.

 

[Leftyretro]

I have a data sheet, I bought the sensor new from Automation Direct. It's a NPN type, normally open, 10-30 VDC 200 MA max.

Those are pretty standard industrial sensors. They are open collector NPN and usually have 3 wires, power, ground, and open collector switched. Would need to know the voltage as well as the current (you said 1 amp?) of the solenoid being used as well as if it's AC voltage or DC voltage. This is a pretty simple application, but need to know the all the details to suggest a final hook-up.

Lefty

 

[DAlgie]

Sorry for the slow reply. The solenoid I am trying to drive is an air valve, it is 110 VAC, 11 watts. The proximity sensor is a NPN type, normally open, 10-30 VDC 200 MA max. I am thinking I will have to put this all on a small PCB of course, but need to know exactly what to use, etc. The power supply, etc isn't a problem for me, but the device to convert the signal from the prox to useable switching gear is.
DaveA.

 

[Leftyretro]

Sorry for the slow reply. The solenoid I am trying to drive is an air valve, it is 110 VAC, 11 watts. The proximity sensor is a NPN type, normally open, 10-30 VDC 200 MA max. I am thinking I will have to put this all on a small PCB of course, but need to know exactly what to use, etc. The power supply, etc isn't a problem for me, but the device to convert the signal from the prox to useable switching gear is.
DaveA.

You are going to need a relay to interface between the sensor open collector output and the 110vac circuit to energize the solenoid. The coil voltage of the relay should match the voltage of your small power supply that the sensor needs anyway, say 24vdc and will have to have a current capacity of the sensor and the relay coil. 1 amp might be enough but that depends on the specific relay you use.

One lead from the relay coil will wire to 24vdc and the other coil lead will wire to the open collector output of the sensor. The relay contacts should be rated for 120vac or higher service. The solenoid 110vac circuit will wire in series with the common and normally open contacts of the relay.

Make sense?

Lefty

 

[DAlgie]

So just a basic 24VDC relay will switch from the prox, simple enough. You have a preference for a relay, SSR or a mechanical type?

 

[Leftyretro]

So just a basic 24VDC relay will switch from the prox, simple enough. You have a preference for a relay, SSR or a mechanical type?

As long as the relay coil doesn't require too much current as your sensor's open collector does have a maximum limit, what 200ma?.

I kind of like the standard 24vdc electromechanical relays like potter Brumsfield and such, Some even have a small lamp near the coil to show you when it's energized. We used hundreds of these in the refinery I worked in.

Lefty