AD8495 and thermocouple

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jaleb
 
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AD8495 and thermocouple

Post by jaleb »

I've to connect thermocouple sensor to AD8495.
Is there any possibility to use AD8495 with python? I've searched but there is no Python Library.
Instead for MAX31855: https://learn.adafruit.com/max31855-the ... y/software
Anyway how can I use AD8495 to read temperature in another language?
Thanks.
Last edited by jaleb on Thu Feb 11, 2016 5:09 pm, edited 1 time in total.

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adafruit_support_mike
 
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Re: AD8495 and thermocouple

Post by adafruit_support_mike »

The AD8495 has analog output, so you can connect it to the BBB's ADC.

The conversion formula is (Vout-1.25v)/0.005v = degrees C.

One thing to note: the BBB's ADC only accepts input up to 1.8v, but that would correspond to a temperature of 110C. If you need to go higher than that, drop the output with a voltage divider.

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drewfustini
 
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Re: AD8495 and thermocouple

Post by drewfustini »

[Looks like we were typing at the same time ;) ]

The MAX31855 is a digital sensor connected SPI, and its library wouldn't be applicable to AD8495.

The AD8495 is an analog sensor so it will need to be connected to the ADC on the BeagleBone:
Setting up IO Python Library on BeagleBone Black: ADC
Measuring Temperature with a BeagleBone Black

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jaleb
 
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Re: AD8495 and thermocouple

Post by jaleb »

adafruit_support_mike wrote:The AD8495 has analog output, so you can connect it to the BBB's ADC.

The conversion formula is (Vout-1.25v)/0.005v = degrees C.

One thing to note: the BBB's ADC only accepts input up to 1.8v, but that would correspond to a temperature of 110C. If you need to go higher than that, drop the output with a voltage divider.
ok! the problem is that I need to go much more higher than 110 °C, almost 400/500 °C. So I think it's better to use MAX31855 connected to a thermocouple.

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jaleb
 
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Re: AD8495 and thermocouple

Post by jaleb »

drewfustini wrote:[Looks like we were typing at the same time ;) ]

The MAX31855 is a digital sensor connected SPI, and its library wouldn't be applicable to AD8495.

The AD8495 is an analog sensor so it will need to be connected to the ADC on the BeagleBone:
Setting up IO Python Library on BeagleBone Black: ADC
Measuring Temperature with a BeagleBone Black
ok at this point is not better and more simple to use MAX31855 connected to a thermocouple?
For example TMP36 ha has low range (from -40°C to +125°C) and I need to go until 400 °C. In this case you need a thermocouple.

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drewfustini
 
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Re: AD8495 and thermocouple

Post by drewfustini »

Yes, I think the MAX31855 would be better for that use case. It also has the advantage of being digital (SPI bus) and there is already that Python library as you mentioned.

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