Earthing/ Grounding Value for PLC

[s_dhamayana 0]

Dear All, I have a doubt regarding earthing/ grounding value for PLC/ Automation especially Allen Bradley PLC, which one is correct less than 1 Ohm or less than 0.1 Ohm ? Any one kind help me ??? Thank you, sonny dha

[BobLfoot 302]

If you are working with ControlLogix the following Manual on Pages 10 and following decribe connecting the ground. Unfortunately it refers to the NEC when describing the fround not an ohmic value. If you are working with a PLC 5 the following Manual on Pages 8 and following describe connecting the ground. Unfortunately it refers to the NEC when describing the fround not an ohmic value If you are working with a SLC the following Manual on Pages 9 and following describe connecting the ground. Unfortunately it refers to the NEC when describing the fround not an ohmic value

[gravitar 3]

As the text is revised every three years, I can't blame them for referring people to the most recent NEC handbook. They're the authority after all, not A-B.

[s_dhamayana 0]

Thank you for all reply, Mr. Sparky, could you help me how i can get this "Industrial Automation Wiring and Grounding Guide Lines Publication 1770-4.1" ? Or any people can explain what is the latest role for Automation Grounding as per the latest NEC ? Thank you, sonny dha

[BobLfoot 302]

You can find a lot you are looking for at the Rockwell Automation Literature Library Home Page. Your publication 1770-4.1 can be found here. Hope this helps.