Distribution panel wiring

This sub panel was supplying a shed for lighting purposes only (3- 15 amp breakers). The supply was a 30 amp single pole breaker in the main panel with 10 gauge wire supplying this panel (note jumper wire). Would there be any harm with this install? If so, how would you write up? Do grounds and neutral still need separatation/isolation?
Any helpful insight appreciated.

In anything other than a service panel the neutrals need to be isolated from the grounding conductors.

The improper jumper is to feed voltage to the other buss.

At best, I would call that an unprofessional installation that should be serviced by a qualified electrician.

There are several issues visible in that installation, and being in a detached structure, it should include its own grounding electrode (i.e. ground rod).

I don’t have my code book with me… but I thought there is something that mentions if a subpanel has 3 or more branch circuits, it needs to be fed via 3 or 4 wire.


Since this is a detached structure it now is required to be fed with a feeder that contains both a neutral and an EGC (equipment grounding conductor). Prior to the 2005 NEC you were permitted to bond the neutral at a separate structure if there were no metallic paths connecting the two structures together. Since there are 3 circuits present then a GES (grounding electrode system) is required. Separate structures served by only one circuit or one MWBC (multi-wire branch circuit) do not require a GES.