GEC for Control Power XFMR

[I-learns]

For something like maybe a small 480/120V control power xfmr used to power contactors, where in the NEC would it not require the whole system bonding and grounding electrode conductors at the level one would need to do for a service or separately derived system that feeds a panelboard, as well as the bonding of the multiple systems per 250.50? They are grounded systems but where would the exceptions be that doesn't require what you would need to do at a service or a seperately derived system that is used to power general loads?

 

[infinity]

1000va or less only require a bonded neutral and no GEC. {250.30(A)(5)Exception 3}

 

[tom baker]

250.30 A 5 exception 3.