The year 2020 provided me with the unique opportunity and the time to produce a series of videos on topics that you told me were of interest to you. I recorded them from my house, and livestreamed them over the course of several months. There were a lot of you that might not have been able to tune in, and others who did, but would enjoy the chance to see them again. We'll be sending them out monthly in a newsletter series. Enjoy and feel free to share!
This video is about where to locate the System Bonding Jumper (SBJ) and what would happen if no System Bonding Jumper (SBJ) was installed at all. This is a very important topic to understand because if not installed correctly serious consequences may occur. Article 250 Grounding and Bonding of the NEC is perhaps the most misinterpreted and misapplied in the Code.
 In a solidly grounded system, the system bonding jumper must be installed at the same location where grounding electrode conductor terminates to the neutral terminal of a separately derived system. There are basically two options as to where to locate the SBJ, either at the separately derived system (transformer/generator) or the first means of disconnect of the separately derived system [250.30(A)(1)]. If installed incorrectly at both locations dangerous objectionable current will flow on conductive metal parts due to improper neutral to case connections. These wiring errors will create neutral current parallel paths on metal parts which can cause electric shock, fires and the malfunction of electronic equipment [250.6].
If no SBJ is installed in a solidly grounded system then in the event of a ground fault the overcurrent protection device will never clear. Essentially you will have a ungrounded system which is a violation of 250.20(B) that states whenever a neutral conductor is used as a circuit conductor the electrical system is required to be grounded. Take the time to watch this video where I explain everything you need to know about “System Bonding Jumpers” and why they are an integral part of ensuring a safe electrical installation!
Click here or on the image to watch the video [5min:56sec].
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