sensors in Industrial environment

Hello all
I want to deploy some IOT applications in an industrial environment. TO connect sensors to Arduino what type of cables should I use so that I can avoid noise and these should also be long enough (eg 1/2 meters)
Atul

Depends on the sensor types , analog/digital etc

What are you proposing ?

I have temperature , proximity, load and ultrasonic level sensor which will feed data to the Arduino. from the arduino i will stream data via ethernet cable and also operate a relay to turn an AC motor on/off. Most sensors are analog, but will also consider digital

You have to give the part numbers of the specific sensors, this is too generic to suggest cables.

Also it doesn't matter if you have super rugged cables if your sensors are not ruggedised to the same extent.

What kind of industrial? Wet? Big magnetic fields?

0.5m is usually never a problem. I2C is the only protocol which requires special care in the 0.2-1.0m range and is totally unsuitable for >1m

Im planning to use LM35 and DS18B20 for temperature sensing.
For proximity im searching for a sensor that can detect the end of a roll (edge detection) (DC 6-36V Inductive 4mm PNP-NO ??)

WHat type of cables can be used to carry data from these sensors to Arduino in a industrial environment which is usually dry ?

Use a 3-wire cable for the DS28B20's. Just anything stripped off the side of a ribbon cable or leftover from another project.

There is no advantage and several disadvantages to using the LM35 instead of the DS18B20 with an Arduino. Use the good sensors.

Why did you specify a 6-36V sensor to use with your 3.3V Arduino? I would always look for 3.3V sensors. Unless I already had the sensor elsewhere in the plant and wanted to keep them all the same.

In the industrial setting, you are always concerned with other devices that might influene any part of your system.
it is not uncommon for a guy with a radio to walk around and report things going on. You need to make sure you have wires, not antennas.

I would want sensor wires to be short and have shielding.
my CAT-5 cables are shielded and I have glands to connect them into my gasketed enclosures. I use PG-7 glands

You said you will stream via ethernet cable.
Does that mean you will be using a CAT-5 (or similar) as your wires ?
Or that you will be using Ethernet for your communications ?

Im trying to see whats the best possible wire for industrial application. I can use CAT5, not sure what i can use to secure the sensors. Crimp connectors etc ???

atulkatti:
Im trying to see whats the best possible wire for industrial application. I can use CAT5, not sure what i can use to secure the sensors. Crimp connectors etc ???

If you have an electrical contractor you bring in for work, ask them about low voltage wire and wiring.

Paul

thanks
What would be a good temperature sensor with range between 0 to 250C , compatible with the Arduino in industrial environment, running 24 X 7

That’s a pretty big range. I don’t know of any digital sensor that can do this; so you have to look at analog ones.

I’m thinking of a thermistor, those can handle the range and are nigh indestructible, but they’re most sensitive in a 50-100° span. The rest of the range the precision will be limited. A higher resolution ADC and good quality pull-up resistor do help a lot here.

A thermocouple is another possible solution, even more indestructible than a thermistor. They should be able to handle the full range, I’m not familiar enough with them to know the precision over such a range.

atulkatti:
Im trying to see whats the best possible wire for industrial application. I can use CAT5, not sure what i can use to secure the sensors. Crimp connectors etc ???

the answer to “the best possible” is that the application drives the selection
whatever meets the APPLICATION, that drives the selection
if you have a kiln and want a temperature reading, then your application drives the selection.
if you only want to measure a furnace temperature, and your wires are not inside, then your application drives the selection.
if you want to measure the air conditioning in your computer server room, your application drives the selection
if you want to run wire inside of an HVAC duct, your application drives the selection.
you can get armored cable, look at thermocouples or garage door open sensors.
you can get teflon coated cables when wear is a concern
the reason for so many selections is that there are so many applications.
you might say, that simply, the application drives the selection.

MorganS:
There is no advantage and several disadvantages to using the LM35 instead of the DS18B20 with an Arduino. Use the good sensors.

The LM35 is analog. You can get higher resolution and more instanious readings.
The digital interface of the DS18B20 is not real time.
Also you can do data manipulation if your chosing vs. The canned smoothing done by the DS18B20
One of the disadvantages is that you have to calibrate.
But you must ververify calibration of the DS18B20. They are not all good out of the box.
As a note read the data sheet for the LM35 about using a cap on the lines. Solves some of the spurious readings issues.

my requirement is to insert a temp sensor in a MS heating pad. The temperature range is 0 to 250. Not sure if LM35 /DS18B20 can serve the purpose. But it needs to be long lasting and reliable. one requirement is that if the temp goes below a set temp, then we need to turn off a motor. so the reading needs to be precise and instantaneous

DS18B20
Temperature Sensor and EEPROM
Measures Temperatures from -55° C to +125°C (-67°F to +257°F)
±0.5°C Accuracy from -10°C to +85°C

================

The LM35 device is rated to operate over a −55°C to 150°C temperature range,

====================

350 either F or C is outside of the spec for those.

I am thinking maybe a T or K thermocouple.
lots and lots of options for the sensor size, from a grain of sand to a thermowell.

you can get a K type thermocouple with accuracy of a few degrees and a speed of response in real time.

=====================

As a note, temperature is not instantaneous. that is why the D in PID does not work for temperature control.
Temperatures have a rise time, all you need to have is a sensor whose response time is better than the rise time of the heating element.

ditto for the low limit.

if the heating pad temperatures are up to 35 deg C. then either could work.
I would suggest you get both types and experiment.
I would even offer that a thermocouple might be the better choice due to the wide range of probe designs.

“instantaneous” doesn’t exist. Faster sensors will have a delay of a few seconds or less. Many motors take a lot longer than that just to spin down. It also depends on how fast your temperature actually changes.

Precise: define the allowed error. No sensor is absolute, 1-2°C error is normal for cheap sensors. <1°C for most such sensors if you do careful calibration. <0.1°C for high end calibrated sensors (comes with matching price tag).

By the way, if you’re not sure if a sensor can handle a certain range, check the data sheet. That and much more information about the sensor can be found there.

Thank you very much for the help. Im inclined now to go towards thermocouple. Only issue is that since the output voltage is low, need a good amplifier inbetween the thermocouple and Raspberry Pi.

Yes, they need an amplifier. Such amplifiers are readily available. E.g. AD595, MAX31855 or MAX6675 modules.

ok ...any advise on the selection of pressure (20-25Kg) and photoelectric sensors (PE)? need PE to detect the end of a plastic roll