How well do you know the Code? Think you can spot violations the original installer either ignored or couldn't identify? Here's your chance to moonlight as an electrical inspector and second-guess someone else's work from the safety of your living room or office. It's your turn to identify the violation.
Hint: Funny looking service disconnect
Find the Answer
Section 250.94 of the 2014 NEC requires an intersystem bonding termination for bonding of other systems to be installed external to enclosures at the service equipment, metering equipment or building disconnecting means. Although the branch circuit supplying this receptacle and its enclosure are none of those things, it’s still a violation.
The intersystem bonding termination shall comply with the following:
1) be accessible
2) allow for connection of at least 3 bonding conductors
3) not interfere with opening of enclosures
4) be securely mounted and bonded to metallic service equipment or metering enclosures or be installed at one of these enclosures and bonded with a minimum 6 AWG conductor to the enclosure or GEC
5) be securely mounted and bonded to the building disconnecting means or be installed at one of these enclosures and bonded with a minimum 6 AWG conductor to the enclosure or GEC
6) The terminals must be listed for grounding and bonding.
According to the Exception, an intersystem bonding termination is not required for existing buildings. An accessible external means shall be permitted at service equipment and building disconnecting means by one or more of the following:
1) an exposed nonflexible service raceway
2) an exposed GEC
3) other approved means for externally bonding to the GEC, grounded raceway or equipment.