how to connect AD595 thermocouple amplifier?

[jex · Accepted solution]

Hi Wallice:

Do u have a data sheet about AD595? read the data sheet, it will mention that it has 10mV/degree C. So just put a multiplier so that it can be convert 1V=1C.

[Arash_pake]

Hi.I have problem with ad595 too.i have a K type thermocouple.when i connect it to ad594(i know its for j)it kind of work.but when i connect ad595 to power +5v the alarm turns on.even when i connect pin 1 and 14 together.what is the problem

[Sama]

Dear Arash

There is a diagram there about how exactly to connect but seems you already saw that, the AD595 produces linear analog signal of 10mV/C this acquiring 5 volts means you need 500 C minimum read by the thermocouple ( I am assuming K type) . 

please elaborate more the configuration you need to be able to help you.

thanks for your time

[Sama]

Dear Arash

please review this diagram and make sure this is how you connect.

thanks

[Arash_pake]

yes my digram is like that.like i said when i change it to ad594 ,it works so the wiering should not be the problem(594 and 595 are pin compatible).another thing,can we use ad594 for k type without recalibrating in hardware and only change a factor in digital number?

[punit]

hi howdy,

  i have connected my ic and thermo couple as you suggested. and i am measuring voltage signal through NI daq card. i am gettting good result for temprature greature than 35 degree centi. but when temprature goes below 35 . my ic is giving constant 350 milivolt signal it does not go below. means am able to measure only minimum temp 35 degree. my roop temp is 20 degree . and one more thing should we sort pin 8 and 9 or not. if not than what to do with pin 9.

thank you

punit kumar

iit bombay

[shrutimv]

Iam facing a problem with AD 595. The output of AD 595 is connected to a digital indicator which shows the the output in millivolts.  Iam using K type thermocouple( chromel-alumel). As the temperature of the thermocouple junction increases beyond 200 degree celcius the output of AD 595 stops at 2078 mV.  For Further increase in temperature there is no raise in output...The output remains the same for higher temperaures.... IC pin connections are as follows, pin 1-chromel (directly connected to the pin), pin-14 alumel (directly connected to the pin), pin-1,13,4 ground, pin 11-+12VCC,pin 7- -12VCC, pin 8 & 9 interconnected and output is measured between this interconnection and ground. at room temperature of around 26 degree celcius the output of AD 595 is 266mV.

Plz help...

[shrutimv]

Iam facing a problem with AD 595. The output of AD 595 is connected to a digital indicator which shows the the output in millivolts.  Iam using K type thermocouple( chromel-alumel). As the temperature of the thermocouple junction increases beyond 200 degree celcius the output of AD 595 stops at 2078 mV.  For Further increase in temperature there is no raise in output...The output remains the same for higher temperaures.... IC pin connections are as follows, pin 1-chromel (directly connected to the pin), pin-14 alumel (directly connected to the pin), pin-1,13,4 ground, pin 11-+12VCC,pin 7- -12VCC, pin 8 & 9 interconnected and output is measured between this interconnection and ground. at room temperature of around 26 degree celcius the output of AD 595 is 266mV.

Plz help...

[ongeelim]

Hi shrutimv,

I would recommend you to create a new post for your problem.

Anyway, what DAQ hardware are you using to acquire voltage signal? And what is your maximum and minimum value setting and other DAQ settings for your DAQ in LabVIEW (I presume you're using LabVIEW)?

-Ee Lim-

[shrutimv]

iam not using any DAQ hardware...iam just using a digital indicator(does the job of multimeter to display voltage in mV).  It shows maximum of 2078mV though the temperature is raised upto 400 degree celcius.  i thought it cud b the problem of supply voltage to the IC which was 5 volts before and hence changed to 15volts...in spite of which i get the same voltage