wiring a liquid level sensor

[kuhli]

I'm messing around with the equivalent to honeywell LLE105000 optical liquid level sensor and I'm a bit new to electronics.

The way I read the diagram the red and green should make a completed circuit when the sensor is out of water, and the circuit should be broken when in water. I'm using a 4.8v 0.4A transformer to energize the circuit and I'm not getting a change in voltage regardless of the sensor being wet or dry.

Can anyone with some experience with such things share an idea?

The guide for wiring is here:

 

[Donw]

If your using the HW LLE in SW your going to have problems in the long run. The material needs to be modified by HW to hold up to SW.

As far as the wiring goes. You have three wires 5-12dc + going to the red - goes to the blue. What is going to happen is when the sensor is dry there will be NO ground on the green output wire. When the sensor is wet there WILL be - on the green output wire.

This is the oposite of what you would generally see with the use of a float switch. You just need to reverse the logic and use that to control the load or load relay.

Don

 

[kuhli]

I'm using them in freshwater not salt so I should be ok there. Also, the version I'm using is built by the company that makes em for Honeywell and it closes the circuit when its dry and opens it when dry so there shouldn't be a relay required.

With that out of the way I remain a bit confused, if I'm to wire this into my aquacontroller how might I do so? What would the circuit be in that case?

Also, just to be clear and restate what you said:

+ve to red
-ve to blue
ground on the green switches with the state of the switch.

Thanks for the help

 

[Donw]

<a href=showthread.php?s=&postid=11963083#post11963083 target=_blank>Originally posted</a> by kuhli
I'm using them in freshwater not salt so I should be ok there. Also, the version I'm using is built by the company that makes em for Honeywell and it closes the circuit when its dry and opens it when dry so there shouldn't be a relay required.

With that out of the way I remain a bit confused, if I'm to wire this into my aquacontroller how might I do so? What would the circuit be in that case?

Also, just to be clear and restate what you said:

+ve to red
-ve to blue
ground on the green switches with the state of the switch.

Thanks for the help

If the sensor is equal to the 105000 then its a dry on that is not correct. Opticals are backwards of what you would normaly concider "on".

If you going to connect to a aquacontroller you dont need to be concerned with the logic, just reverse it in the controller programming.
What you need to do is back probe the ac's power supply + wire with your dvom. Then back probe the ac's IO signal with the other lead of your dvom. If you get 5-12vdc then connect the blue wire to the IO signal and the green to the IO input then the red to the ac's PSU + wire.

If you dont get the above senerio then you will need a relay.

Don

 

[kuhli]

Indeed if the switch is dry the state is on, wet and the state is off. All would be fine if I were to only one switch but since this is a topoff system I'd like some redundancy.

Can anyone shed some light on how to wire two of these so that if either showed wet(off) that the circuit would be broken?

 

[kcress]

This is also a DC circuit. You can not run it with a transformer. You need a DC power supply.

A wall wart.

 

[Donw]

<a href=showthread.php?s=&postid=12108577#post12108577 target=_blank>Originally posted</a> by kuhli
Indeed if the switch is dry the state is on, wet and the state is off. All would be fine if I were to only one switch but since this is a topoff system I'd like some redundancy.

Can anyone shed some light on how to wire two of these so that if either showed wet(off) that the circuit would be broken?

If the switch is as you assume its simple. Use one switch to power the other.

Don