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External powersupply for the DS18B20?


Question

Posted

Hi, I need 26m of cable for 4st DS18B20 sensors (2x8m and 2x5m). Is it possible to power the sensors itself with a 5v external power adapter and just connect the data channel to the "universal binary sensor"?

 

Universal Binary Sensor
FGBS-001

 

5 answers to this question

Recommended Posts

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Posted (edited)

I think - no.

Sensor is powered with 3.3V and the problem is not power supply, but capacity of the cable.

if You need longer distance, You can try to connect all of them and it should work(28m is possible) but probably You will lose communication with first power los.

 

read topics about smart implant and issue with lack of communication after power reset

 

to extend the distance add a 4.7k Ohm resistor between the power supply (VCC) and the data pin, add an electrolytic capacitor on the sensor power supply and before the implant. I also add a 100nF capacitor on the implant power supply and the sensor itself

 

Edited by GanzConrad
  • 0
Posted (edited)
On 4/23/2025 at 1:50 PM, Sherman762 said:

Hi, I need 26m of cable for 4st DS18B20 sensors (2x8m and 2x5m). Is it possible to power the sensors itself with a 5v external power adapter and just connect the data channel to the "universal binary sensor"?

 

Universal Binary Sensor
FGBS-001

 

Connect your DS18B20s according to the Universal Binary Sensor or Smart Implant manual and it will work.
You do not need to use a separate power supply for the sensors.
I have had 4 sensors on 35m of cable and it has worked.

Edited by RH_Dreambox
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  • Inquirer
  • Posted
    On 4/26/2025 at 3:24 PM, RH_Dreambox said:

    Connect your DS18B20s according to the Universal Binary Sensor or Smart Implant manual and it will work.
    You do not need to use a separate power supply for the sensors.
    I have had 4 sensors on 35m of cable and it has worked.

     

    Well, it doesn't work, that's why I'm asking... I've now tried many different ways and can't get it to work. It seems that the two 8m long sensor cables are destroying it. I will now connect two shorter ones to a smart implant and the two 8m long ones to each UBS. Not super duper, but the most important thing is that it works.

    • 0
    Posted
    5 hours ago, Sherman762 said:

     

    Well, it doesn't work, that's why I'm asking... I've now tried many different ways and can't get it to work. It seems that the two 8m long sensor cables are destroying it. I will now connect two shorter ones to a smart implant and the two 8m long ones to each UBS. Not super duper, but the most important thing is that it works.

    There are a few things to consider when mounting DS18B20 sensors to UBS or Smart Implant.


    1. it is important to connect all the sensors before including the UBS or Smart Implant to the HC controller.

    It will not work to connect a sensor after inclusion. You will have to exclude and then include the device again.


    2. the DS18B20 is a 1-wire sensor and it can be connected as a ‘serial’ device. That is, you can have a single long cable and hang the sensors with shorter branches from the main cable.

    You don't have to connect them in parallel to the UBS or Smart Implant. This is how I connected my sensors, and no separate power supply is needed.

    • 0
  • Inquirer
  • Posted

     

    On 4/28/2025 at 3:25 PM, RH_Dreambox said:

    There are a few things to consider when mounting DS18B20 sensors to UBS or Smart Implant.


    1. it is important to connect all the sensors before including the UBS or Smart Implant to the HC controller.

    It will not work to connect a sensor after inclusion. You will have to exclude and then include the device again.


    2. the DS18B20 is a 1-wire sensor and it can be connected as a ‘serial’ device. That is, you can have a single long cable and hang the sensors with shorter branches from the main cable.

    You don't have to connect them in parallel to the UBS or Smart Implant. This is how I connected my sensors, and no separate power supply is needed.

     

    1 yep, i'm a specialist at that now... remove, change cabels, add... and repeate...

     

    2 problem is that the point of intrest is spred out on quite a big area... i did make a really simple sketch to show how it works. it looks like i will use 3 UBS for this to make it work. 1 for the 3meters sensors and 2 for the 2 8m sensors... 

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