Ds18b20 wiring into more than 15m

Using Arduino Sensors
1

I would like to ask if it is possible to wire multiple DS18B20 every 1m up to 15meters distance? if it is so, what would be the size of wire and what is the resistors needed and what would be the wiring diagram.

2

It is possible but I would expect it not to be very reliable. I would start with a ???? K resistor (3K for 5V and 2K for 3V). Also I suggest you use shield wire as I have no clue to where it is going.

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3

Thank you for your answer. I am planning to use it in different water tank just to monitor the water temperature inside the water tanks. the wire of the ds18b20 would be enclosed into a pvc pipe. I'm planning to use ESP32 but also not sure of it.

4

Then power the sensor from 5volt (V+ or Vin of the ESP),
and pull up with ≥ 1k to the 3.3volt pin of the ESP.
Leo..

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5

Hello yourstruly_trulyyours

Reading the data sheet might help.

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6

Then you have several I/O, dividing your network into zones will make it more reliable. It will be very wise to read @paulpaulson's link.

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7

Generally for a single DS18B20 you would have:

Pullup Resistor guide
    Length       5.0 Volt  3.3 Volt
    10cm (4")     10K0      6K8
    20cm (8")     8K2       4K7
    50cm (20")    4K7       3K3
    100cm (3'4")  3K3       2K2
    200cm (6'8")  2K2       1K0

A result of -127 degrees indicates a sensor error

It should be quite similar for multiple sensors on one branch, just adjust the pullup resistor value a little to ensure you get reliable data.

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8

Thank you. I will try this in actual setup.

9

is this applicable even if the ds18b20 I have is generic or not original? the sensor from china is cheaper but still working when I program it by address not index