ESA Technical Advisor, Trevor Tremblay, reveals how meter bases can go from simple to seriously risky if installed incorrectly.
As code enforcement around meter bases ramps up, contractors must stay sharp, read all rules carefully (especially those “notwithstanding” clauses), and double-check labeling. With the right education and planning, the transition can be safe, seamless, and built for the future.
In this episode, ESA Technical Advisor, Trevor Tremblay, joins new host, Saira Husain, to walk through common mistakes, updated code requirements, and best practices for bonding and grounding meter bases, especially in the lead-up to the October 2025 enforcement deadline.
Bonding Confusion at the Base
Improperly bonded meter bases have become a recurring issue in the field. With updated Section 10 code rules introduced in 2018 and a transitional period in place until October 1, 2025- many electrical contractors are still relying on old habits. This is especially true since new meter bases look almost identical to legacy models, making it easy for old habits to persist.
“We are seeing a lot of meter bases being installed without a bond unknowingly,” Trevor explains. “It's pretty concerning. There is a chance that in abnormal conditions or when something doesn't work properly it could sit there energized.”
That can lead to dangerous results, including shock or fire hazards. Trevor says that while the code changes may be subtle, they’ll have a “pretty big impact on installations.”
From Habit to Hazard
For decades, contractors bonded meter bases through the neutral. When the rules changed, that practice became non-compliant. Trevor’s concern is that many Licensed Electrical Contractors may have missed that update.
“We are creatures of habit,” he says. “We've been doing something the same way for 20-30 years and we don't get a defect, so we continue to do it the same way.”
But in 2018, Section 10 got a “complete rewrite—essentially saying your neutral now could only be grounded in one location, at the consumer service. No longer can you do the meter base at the panel board.”
Subtle model differences like “permanently bonded” vs. “isolated neutral” often appear as small labels or acronyms (e.g., “IN”) in hard-to-see places.
Trevor recommends verifying bonding using a multimeter whenever there's doubt and paying close attention to the manufacturer’s specifications. Some newer models even have visible bonding conductors to help identify the configuration more easily.
Multi-Gang and Armoured Cable Considerations
Contractors also need to pay close attention when working with multi-gang meter bases or armoured cables. As Trevor notes, the new code requirements allow for a single bonding jumper at the meter base and reduce the number of required ground bushings—provided bonding conductors are properly installed.
“In the new code cycle now, if the bond wire is run with the conductors, you only have to put one ground bushing at either end of the teck cable, and if you have a bond wire in there, you connect it at both ends,” Trevor notes.
“Essentially, we did end up paralleling the neutral with the armor and hence the ground bushings. They wanted a good connection just in case you lost the neutral.”
Trevor also highlights that contractors should take note that as of October 1st, 2025, when it comes to multi-gang setups, grounding is only permitted at the meter base, and a system bonding jumper must be installed.
“It eliminates the need for multiple ground electrodes and the requirement to interconnect all the ground electrodes when installed at the same building,” he says. “These meter bases should have enough termination points for all the bonding and grounding conductors required.”
Combination Devices & Replacement Guidance
Combination meter mounting devices-—which house the meter and main breaker—require grounding in the breaker compartment—not the meter area. It’s another subtle but important distinction.
What about meter base replacements? Trevor explains that if the configuration and ratings don’t change (e.g., replacing a 200AMP underground base with the same type), contractors won’t be forced to upgrade to meet new grounding rules.
“Aging infrastructure leads to failures, so we would recommend changing it no matter what.”
The ESA’s bulletin on whole-home transfer switches has already been updated to reflect the upcoming grounding rules. While the code is not retroactive, contractors should still install systems that meet new requirements to avoid rework in the future.
Until the deadline, ESA inspectors will be issuing postponements, giving contractors time to adjust and educate themselves about the single-point grounding requirement.
More information on these, and other updates, is available on our website.
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