sub panel

[mickeyrench]

we installed a 200 a service single phase and a sub panel . i used 3 wire bx
to the sub . is this ok or do i need 4 wire bx? thanks for any help
yes, we used ac cable. thanks again

 

[Dennis Alwon]

we installed a 200 a service single phase and a sub panel . i used 3 wire bx
to the sub . is this ok or do i need 4 wire bx? thanks for any help

Article 320.108 appears to allow AC cable as an adequate path for equipment ground. I am assuming by BX you mean ac cable