2 Wire + Braided ground

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DW98

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existing loadcenters have a 2 wire + braided ground SE type cable from the meter center. installation was in the early to mid 70's. There is not a separate grounded conductor. The grounded conductor and equipment ground must have been bonded at the loadcenter. Was this an acceptable code approvded installation at the time?
 
The location of the Service Disconnect(s) and the Main Bonding Jumper(s) determines the point at which the "Grounded Conductor" and the "Equipment Grounding Conductor" become separate from each other.

On the Power Company side of the Main Bonding Jumper(s) in the Service Disconnect(s) the "Grounded Conductor" merges with the "Equipment Grounding Conductor" and become the "Service-Entrance Grounded Conductor".
 
The meter centers have 100A circuit breakers so the service entrance ground should be established there. However, the grounded conductor must have been bonded to the braided ground at the loadcenter. I'm wondering if the ground was also allowed to serve as the neutral conductor in earlier installations. Somewhat analogous to the old two-prong receptacles.
 
100A circuit breaker is located at meter center, so grounded conductor - equipment ground bond was established incorrectly at loadcenter. was code different in the past or less strict that would have allowed this. The braided shield was essentially a current carrying neutral.
 
DW98 said:
was code different in the past or less strict that would have allowed this.
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The National Electrical Code wasn't that different, not in the '70s. From you description, the main bonding jumper should be at that first 100 Amp circuit breaker (the service disconnect) in the meter center. The Grounding Electrode Conductor should be going out to that meter center.

In the jurisdictions I've worked in, I'd have a four wire SER cable coming to the circuit breaker panel, and would float the neutral in the panel.

Now, the enforcement of the Code, that's another manner. For that answer, you have to look to the actual history of the jurisdiction that this set of panels and meters is in. Find an old timer there that knows.
 
Sorry for the piecemeal nature of this post. I didn't look at the loadcenter feeders at the time of my design. I was just extending the existing feeder to a new loadcenter as part of a rennovation. At demolition, the 2 wire + woven/braided ground was discovered. Also, I've since found out yesterday that the meter centers do not have a neutral or ground bar, according to the utility. I'm hoping to get a look at this. In either case, these bars should be installed and the grounded conductor run to the service entrance to bring things up to code.

The code official would allow the existing installation to remain if supported by the NEC, but I haven't found anything that will support grandfathering this installation.
 
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