Hi,

I have a E& H thermometer model No:TR66 and S7 1200 PLC (6ES7 212-1HE40-0XB0)

E &H thermometer provides 4 to 20 Ma output.

S7 1200 plc  analog input is 0 to 10 V.

So please guide whether we need to connect resistance in between Analog input in PLC?If so how much Ohms resistance we need to connect..

Also please guide on the wiring diagram also.. 

2M ,0..here how to connect the TR66 E and H to PLC..

Thanks ..

Hello,

maybe simple Ohm law can help 

As per calculation we need to connect 500ohms .2watt resistor.. Please confirm..

Also please let me know how to wire from E and H to PLC ??

 Can you confirm power rating of the resistor which need to use ?? If we use .2 watt resistor  will it  blow out ??? Or we have to go with higher power rating ..Please guide ..

This is my first project with the resistors.. So If you have tried with the resistors , your valuable feedback will be too useful..

0_Einstein

Are you not able to configure your S7-1200 analog input as 0-20mA or 4-20mA?  I know sometimes the answer is yes, and sometimes the answer is no.  If you have already looked and know the answer, that's fantastic.  However, if you were not aware it was possible and had not looked, now you can look, possibly configure for 4-20mA or 0-20mA and wire it right up according to the reference wiring diagram from the s7-1200 system manual.

You can perform an online search for electrical engineering solutions to all kinds of problems.  If you took basic electrical engineering course work, you should be able to figure out how to convert a 0-20mA or 4-20mA single to 0-10V or 2-10V DC with that 500Ω resistor.

kmansal

As per calculation we need to connect 500ohms .2watt resistor.. Please confirm..

Also please let me know how to wire from E and H to PLC ??

thanks all for responses..

https://support.industry.siemens.com/cs/ww/en/view/67396370

siemens recommend to use atleast 1.16Watt..so better to go with 2Watt 500 ohm resistor

0_Einstein

Having a safety margin of 1 in electronics is not a good idea without better knowledge of the system.

I am not going to design your system for you, nor should anyone else without intimate knowledge of the system and how it will act in every possible situation.

Using 1/4 or 1/2 W resistors adds safety margin at virtually no additional cost, unless you are ordering millions of them. Then you can pay a professional engineer to analyze every situation and optimize the size to save a very small fraction of the project cost - but worth it for something where you will use million or more items.

kmansal

 Can you confirm power rating of the resistor which need to use ?? If we use .2 watt resistor  will it  blow out ??? Or we have to go with higher power rating ..Please guide ..

This is my first project with the resistors.. So If you have tried with the resistors , your valuable feedback will be too useful..

0_Einstein

Are you not able to configure your S7-1200 analog input as 0-20mA or 4-20mA?  I know sometimes the answer is yes, and sometimes the answer is no.  If you have already looked and know the answer, that's fantastic.  However, if you were not aware it was possible and had not looked, now you can look, possibly configure for 4-20mA or 0-20mA and wire it right up according to the reference wiring diagram from the s7-1200 system manual.

You can perform an online search for electrical engineering solutions to all kinds of problems.  If you took basic electrical engineering course work, you should be able to figure out how to convert a 0-20mA or 4-20mA single to 0-10V or 2-10V DC with that 500Ω resistor.

kmansal

As per calculation we need to connect 500ohms .2watt resistor.. Please confirm..

Also please let me know how to wire from E and H to PLC ??

 

 

Great example of jargon given to one who nicely asks for help. 
https://www.support.aceautomation.eu/knowledge-base/convert-4-20-ma-to-0-10-v-using-a-resitor/