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EV Charger Wiring
Cable length and mounting height decide whether you like the install a year later. An EV charger is a continuous load, which means it is sized differently from an outlet you plug a tool into.
EV Charger Wiring in O’Fallon and across St. Charles, St. Louis, Lincoln and Warren counties.
Clint Ehman does the work himself. Seventeen years in the trade, Infinity Electric since June 2022.
5.0 from 94 Google reviews · BBB A+ since 2022
What this work actually involves
The circuit is sized for continuous duty and run on its own breaker, with the disconnect where the code and the inspector expect it.
First the reading, then the explanation, then the repair scoped to what was actually found. If that turns out smaller than the job you called about, that is what you are charged for.
Work needing a permit gets one and work needing an inspection is left ready for it. There is no handoff between whoever quotes and whoever fixes, because they are the same person.
When people call about this
- Wanting a second charger
- A charger moved from an old house
- A new EV on order
- A charger that trips mid-session
Why people choose Clint for it
One person does the diagnosis and the repair, so nothing is lost between a salesman and a technician, and nobody is paid to sell past the finding.
Seventeen years in the trade, four of them running his own shop, 5.0 from 94 Google reviews, and an A+ BBB accreditation held since 2022.
Where this is done
Thirty towns across five jurisdictions, worked out of O’Fallon. The housing stock and the inspection process both change as you move across them.
See the full service area, or the rest of our ev charging work.
Load management instead of new service
Load management lets the charger share capacity with another large appliance rather than adding to it. The charger backs off while the range or the dryer runs, then resumes. For a car sitting in a garage for ten hours, that pause costs nothing.
It is code-compliant, it is far cheaper than a service upgrade, and it is the answer a great many houses around here should be getting instead of a quote for new service.
Where the charger goes and why it costs what it does
The run from the panel to the parking spot is usually the larger part of the install. A charger on the far side of a finished garage is a different job from one on the panel wall, and an attached garage is a different job from a detached one.
So the route gets walked before anything is priced: what it passes through, whether existing cavities can carry it, and whether the cable will reach the car’s port with slack on the side it actually parks.
The three answers before a service upgrade
Charging load is the most common reason a house suddenly looks short on capacity, and a service upgrade is only one of three honest answers. The other two are a smaller charger that still fills the car overnight, and load management that shares capacity with the range or dryer.
The load calculation decides which, and you see it. Both alternatives are code-compliant and both are cheaper than new service.
What the car actually needs from the house
A Level 2 charger is a continuous load, which means the circuit is sized at 125 percent of the charger’s draw rather than to its nameplate. A 48 amp charger therefore wants a 60 amp circuit, and that is the number that has to fit inside what the service already carries.
Where it does not fit, there are usually two honest answers before a service upgrade: a smaller charger that still fills the car overnight, or load management that lets the charger share capacity with the range or the dryer. Both are cheaper than new service and both are code-compliant. You get the load calculation either way.
What makes this harder in older housing stock
Across this metro the recurring complications are predictable: no equipment ground, aluminum branch wiring from the mid-seventies, knob-and-tube buried in blown-in insulation, panels that have been added to several times, and splices in places the code has not allowed for decades.
Those turn a simple job into a decision about scope. The decision gets put to you with the reading behind it rather than made quietly and billed.
“Clint came out installed me a large 200 amp panel put some new dedicated lines in my basement and garage he did great clean work all inspections passed he was thorough and knowledgeable. I will have him back out again.”
Jason Holtzman · Google review
How the visit goes
- The call
Which car, which charger, and where it parks. Those three answers decide most of the install before anyone visits.
- The measurement
A load calculation against the existing service, plus the run from the panel to the parking spot and what it passes through.
- The finding
Either the service carries it, or load management lets it share, or a service upgrade is genuinely needed. You hear which, with the number behind it.
- The work
Dedicated circuit sized for continuous duty, disconnect where the code and the inspector expect it, charger mounted so the cable reaches with slack, and a test charge before anyone leaves.
What the job includes
- Load calculation to confirm the service can carry the charger
- A dedicated circuit sized for continuous duty, on its own breaker
- Charger mounted where the cable reaches the car with slack to spare
- Disconnect where code and the inspector expect it
- Permit and inspection where required
- Conduit for a second charger while the wall is open, if you want it
What it does not
- Supplying the charger itself, unless you ask
- Utility rebate paperwork, though we will tell you what exists
- Charging network accounts and apps
If the fix belongs to another trade, you get the name of one rather than a price from this one. There is a gallery of finished jobs, and a form if that is easier than calling.
Related ev charging work
EV Charger Wiring across the metro
Five jurisdictions, five different sets of conditions. What an inspector looks at first differs by address here, which shapes the job as much as the house does.
Warren County
Two kinds of work share the same ZIP codes here: recent subdivisions with modern wiring and tight services, and farm properties carrying several eras at once.
St. Charles County
Twenty and thirty year old subdivisions where nothing has failed and the service is simply at its limit. That is the recurring call.
St. Louis County
This is where the genuinely old wiring lives: cloth insulation, no equipment ground, fuse panels and the mid-seventies aluminum. Each has an accepted remedy rather than requiring a whole-house rewire.
Every municipality covered is listed on the service areas page.
Questions worth asking first.
Do I need a 60 amp circuit for a 48 amp charger?
Yes. Charging is a continuous load, so the circuit is sized at 125 percent of the charger’s draw. That is also why dialing the charger back is often what keeps a house off a service upgrade.
Can two cars share one circuit?
With load-managed chargers, yes, and for most two-car households overnight charging still finishes both. It is considerably cheaper than new service.
Can my panel handle a charger?
Often yes. The load calculation checks what the house already runs against the service rating. Where it is tight, load management lets the charger share capacity instead of forcing an upgrade.
What do your reviews say?
5.0 from 94 Google reviews, and A+ accreditation with the BBB held since 2022. The reviews are on the reviews page with links to where each was posted.
Who actually shows up?
Clint Ehman. Infinity Electric is owner-operated, so the person who answers the phone is the person who measures your panel and pulls the permit. There is no dispatcher and no commissioned salesman.
Tell him what the house is doing.
You will get a reading and a straight answer about what it means, including the answer where the fix is small. EV Charger Wiring in O’Fallon and across the metro.
Mon-Thu 8-5 · Fri 8-4 · Sat 10-3. If a message suits you better, there is a form.