Temperature Transducer Problem

Hello everyone! I had this problem of temperature transducer Phoenix contact Mini MCR-SL-TC-UI. When an error occured as led flashes, it took me several times to switch on and off the machine until the error disappeared. I just want to know what does it means, the measuring range span is less than 50K, in an error diagnostics as the led flashes. Is there any solution to reset the error immediately? Thank you in advance.

There must be a real problem caused by the fault, not just a blinking LED, or you'd leave it alone and go back to work. So, tell us, what does the transmitter do in the fault condition?

Output goes to 22mA?
Output goes to 0mA?

If there's a manual on the web, I couldn't find it in less than 5 minutes.

So my guess is that you have either
- a loose connection that causes a fault;

- a failing thermocouple that causes a fault; one that intermittently goes open or to such a high resistance that it looks like an open circuit, or

- an intermittent problem in the transmitter itself that causes the fault.

Thermocouples should have a low resistance, so a low resistance would not be a fault. A very high resistance could cause a fault, although I was unaware that Phoenix Contact did T/C fault analysis via resistance.

I did find the datasheet HERE. By the way, I hate these little 'pamphlets', with tiny print in 50 different languages. Does anyone write a real manual these days? C'mon... This isn't Twitter, with a 140 character limit...

Just a guess, but maybe it means that the thermocouple is disconnected? The datasheet says that it also flashes when the measured temperature exceeds 1200°C. I'm thinking the 'K' might be Kelvin, since 50°K (-223°C) is the bottom of its range.

I'd suspect a loose connection somewhere.



-Eric

it means the range of the input is too small, choose a wider range (the steps are too big to be a good sensor.

Thank you for the reply. There is no output current nor output voltage. So no control of heat and no temperature signal displayed on HMI. I also checked the thermocouple connection if there had any loose wire and its resistance.Based on datasheet the led is lit when there is sensor break or short circuit. What i have encountered is that the the led is flashing which means the measuring range span is less than 50K and end value for type J is greater than 1200 degress C configured. What is this 50K ,Kelvin or Kilo ohms? Thank you in advance..

They sure don't explain it very well. Who knows... The 'K' might even mean 'Type K' thermocouple...

After seeing your (and shooters) comment, I reread the datasheet. The flashing LED does seems to indicate an incorrect span setting (either too large or too small), yet you can make the fault go away by cycling power, so it really shouldn't be an incorrect DIP switch setting.

Just out of curiosity, what are the current DIP switch settings, and what type of thermocouple are you using?



-Eric

>What is this 50K ,Kelvin or Kilo ohms?

I suspect there's 16 bit A/D converter with 65K counts/steps.

The 50K might refer to minimum number of counts/steps within the range of 65K possible counts.