Surge Protection

[timm333]

Is it a requirement in IEC to use surge-protection-device for digital and analogue pairs coming into DCS from the field? Will it be acceptable in IEC to use surge-protection-device only at 230V power distribution panel supplying power to DCS (and no surge-protection-device for 24V-dc-digital/4-20mA-analogue pairs?)

 

[rbulsara]

230V power circuits are not A/D circuit pairs, and there are specific TVSS devices available for communication/signal circuits. You can draw your own conclusions.

Plus while you can ask IEC, the interpretation of their standards, they are not the enforcing agency, I would think.

Rafiq Bulsara

http://www.srengineersct.com

 

[peebee]

I believe IEC/BS EN 62305 (Lightning Protection) Part 4 (Electronics Devices) might well require it. If you don't have access to 62305, Furse publishes a nice (and free) guide to 62305:

http://www.furse.com/ps/eel/index.cgi?a=getpg&p=Product

Catalogues&b=furse

 

[peebee]

Didn't like the space in the URL... let's try that again:

http://www.furse.com/ps/eel/index.cgi?a=getpg&p=Product Catalogues&b=furse