External Temp Sensor Connected To Fibaro Contact Sensor

Hi all. I am trying to connect an external temperature sensor to a Fibaro Contact Sensor.
the probe is a DROK DS18B20 Temperature Sensor Digital Temp Probe Waterproof.
I am using JJ’s Fibaro FGK-101 Handler.
I have connected the wires from the probe as follows:-

From searching the web I have found the following information about the probe.
Red = VCC.
Yellow = Data.
Green = GND
I have tried various combinations for the wiring and nothing works. The temperature field remains blank.
It could be that the probe is either faulty or I have zapped it with my fiddling with the wires.
Before I consider getting another probe I need to know that it is connected correctly as I don’t want to zap another.
I paired the device as per manual, i.e. paired with temp sensor connected.
So that’s the background over and done with.
Is there anyone out there who has connected one of these temp probes to a Fibaro contact sensor and if so would you mind checking the contact sensor and letting me know which coloured wire goes into which terminal.
Thanks is advance.

@bobbles : your picture is correct (ignoring colors), and the same as in the Fibaro Operating Manual.

I cannot confirm the color coding for your external probe, but Red for Vcc and Green for Ground follows the usual practice.

Your temperature probe may be faulty, but most likely the pairing was done BEFORE you connected your external temperature probe to the FGK-101. It must instead be done AFTER DS18B20 electrical connection.

I suggest you unpair your FGK-101 from the SmartThings hub (using the SmartThings mobile App), then reset the FGK-101 to factory settings, following instructions of §3.2 in the above Fibaro Operating Manual, then electricaly connect your temperature probe, then pair the FGK-101 to the SmartThings Hub, then select my Custom Handler.
You may have to do that more than once before succeeding, since pairing/unpairing in SmartThings is not always 100% reliable.

Hope this helps.

Hi @geeji and thanks for the quick response.
Firstly thanks for confirming the connections.
At least I got something right. :slight_smile:
I had already tried the process you suggested to no avail.
Tried it all again with the same result.
Looks like I zapped the sensor with all my playing.
I’ll order another one and see what happens.
Thanks again for the reply.

Sorry about that.
Before you connect a remote packaged DS18B20, I would suggest you try to connect a NAKED DS18B20 chip directly into the FGK-101. If it works, at least you will know for sure the problem in neither in the FGK-101 nor in the custom handler nor in your pairing process.
If it does not…

Good thinking. At £1 a pop it’s worth the investment.

Just an update.
I did connect a NAKED DS18B20 chip and this reported temp successfully.
My original still didn’t report any temp.
Ordered and connected up a new external temp sensor and this worked OK.
Looks like my fiddling frazzled the original sensor.
Thanks for all he help peeps.
Much appreciated.


You can connect a temperature sensor to a contact sensor’s external terminals? Would that be true if any contact sensor with external terminals such as the Ecolink ones too?