IOLinc & Low Voltage Probe (8015)

[LeeG]

The I/O Linc is expecting Sense to be connected to GND through a dry contact switch to turn the Sense On. Open to turn Sense Off. The specs do not indicate how much if any tolerance there is in either state.

[OmegaQuest]

Do you think if I cut the jack off the probe and just hook the two wires (on the jack side of the probe) to the GND and Sensor screws on the IOLinc it would work?

[LeeG]

Along the lines of anything is possible it could but I really don't think so and it would not allow you to return the probe. It presents like a bad voltage level rather than a bad contact.

[Brian H]

Are you reading the voltages with the probe connected to the I/OLinc?

It maybe using the +5 volts from the I/OLinc to power its internal electronics.

 

What do you measure with the probe connected conected to the jack. Using the terminal block of the I/OLinc for the meter?

Look at the Sensor to Ground voltage terminals. Should be close to +5 volts when not active and close to zero with the bell ringing.

 

My tests showed that the sensing voltage from the I/OLinc had to be pulled to below one volt for mine to trigger. About 800 Ohms from Sensor to Ground was where mine sent the command. I also have seen the Sensor LED glow dimly and the voltage was not pulled low enough to send the command.

 

I have a brand new I/OLInc and will be comparing it to my older ones revision 1.0. On the chance something has changed.

The new revision 1.8 acts almost the same as the old 1.0s.

[OmegaQuest]

The Probe is not connected to the IOLinc when I tested the voltage on the Jack end of the Probe.

 

On the Wire end of the Probe, a reading of 20v is applied when the Doorbell rings.

On the Jack end of the Probe a reading of 0.2v is read when the Doorbell rings.

 

I will check the Ground and Sensor screw terminals on the IOLinc (while the Probe is plugged into the Jack) and see what the voltage reads when the doorbell rings in a few and will report back.

[LeeG]

Thanks Brian for asking that question. I thought the reading was with the probe in the jack.

 

The Sense line on the I/O Linc is not an analog input that is measuring an independent voltage. The Sense input is connected to the I/O Linc 5V source through an internal pullup resister. This keeps a positive potential on the Sense line and keeps the Sensor Off. The expectation is I/O Linc GND will be applied to Sense to turn the Sensor On.

 

For the Sensor not to be turning On the Sense line must not be at or near I/O Linc GND potential.

[OmegaQuest]

This is while the Probe is plugged into the IOLinc.

 

The Ground and Sensoer screw terminals on the IOLinc (without the Doorbell being turned on) the reading is 10.3v

When the Doorbell rings, the reading drops to 8.1v at the screw terminals.

 

Thanks

[Brian H]

Something is not right. The Sensor to Ground should have 5 volts DC on it from its internal sensing circuit.

Measure the sensor to ground on the I/OLInc with the probe disconnected.

Almost sounds like the probe is messed up.

[OmegaQuest]

10.3v when probe jack is unplugged from IOLinc.

 

My meeter is on ACV 200.

 

Thanks

[LeeG]

Change to a low DC scale when measuring the Sense input. That is a 5v DC digital circuit. Not AC.

[OmegaQuest]

Will do.

 

Please hold.

[OmegaQuest]

20 DCV Meeter setting

 

IOLinc GND & S = 5.02v with the Probe plugged in or probe unplugged.

 

When the doorbell rings, the GND & S drop down to 4.12v

 

Thanks

[ELA]

 

My tests showed that the sensing voltage from the I/OLinc had to be pulled to below one volt for mine to trigger. About 800 Ohms from Sensor to Ground was where mine sent the command. I also have seen the Sensor LED glow dimly and the voltage was not pulled low enough to send the command.

 

While monitoring a different IOLINC sensor post I had grounded my IOLINC input and measured 1.7ma. That implied an approx 3K pullup.

That along with your 800 ohms pull pull down also indicate an approx. 1.0VDC threshold.

 

I had been watching this post in hopes I might be able to offer something helpful.

 

Ouch ...

Who would have thought to ask if the meter was on AC or DC

 

 

Now you might go back and do the 18 volt battery test you mentioned in the beginning once again.

[OmegaQuest]

I already did the 18v bat test before I came here to the forums and the sensor never turns to the "On" state.

[OmegaQuest]

I just tried the 18v Bat and still the same

 

The GND & S terminals on the IOLinc while the Probe is plugged in and the 18v Bat is connected to the wire side of the Probe, the meter drops from 5.02v down to 3.6v

[OmegaQuest]

I even tried connecting a 1.5v AA Bat and still the IOLinc only drops from 5.02v down to 3.7v

[LeeG]

There is a polarity to the input side of the probe. Not applicable where AC is input such as the door bell but would make a difference when the input to the probe is DC.

[OmegaQuest]

I tried both ends of the wire on differant +/- combinations. One end drops the v down to 3.7 the other way dosent do anything.

 

So I should have it on the correct polarity.

[LeeG]

Does sound that way and the probe should protect itself from inadvertent polarity error.

 

Although this is very interesting from the technical side, adding more data points to what the I/O Linc Sense needs to turn On, I'm afraid it is not getting any closer to a solution. For whatever reason the probe does not pull the Sense voltage to GND. The last series of measurements of S relative to GND show the probe cannot turn the I/O Linc Sensor On.

 

I think either of the two alternatives, the ELK board or an external AC relay, will provide what you are looking for. Brian has used the ELK board so that is a tried and working solution.

[OmegaQuest]

I like the idea of the ELK option, but it is sold with 2 Doorbell and 1 phone board. I only need 1 of the doorbell boards LOL

[Brian H]

I did a rough sketch of the I/OLincs sensor input.

The Green LED and a few resistors is all part of it.

1.7 ma sounds about correct and mine all toggled at around 1.0 volts or less from Sen to Gnd.

Yes the LED can glow and if Sen isn't below 1.0 volts. It does not trigger.

 

I have a 8015 coming and will see what I can find out.

[OmegaQuest]

Thanks

[Brian H]

I downloaded the 8015 manual from Smarthome.

As a test you may want to try a DC source on the input wires. Manual says White is positive with DC.

My gut says the AC input maybe causing the 8015 to pulse On and Off not triggering the I/OLinc.

Can't do any definitive tests until my 8015 arrives.

[OmegaQuest]

I did try that when I tested the 18v and the 1.5v DC Batterys. Still the same problem.

[OmegaQuest]

I just think its strange that they sell this probe with the IOLinc and say it is for 3-24volt (AC or DC right on the probe itself) yet the sensor or relay never get triggered.