Before the EV Charger: The Load Calculation Nobody Mentions

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<br>The EV charger conversation usually starts in the wrong place. Someone buys a car, looks up Level 2 chargers, picks one rated at 48 amps because more is better, and then calls an electrician to install it. The electrician opens the panel and the conversation changes.
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<br>The question is not what the charger can draw. It is what the house has left to give.
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<br>What a load calculation is
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<br>Every house has a service size, typically 100, 150, or 200 amps in residential Wichita. The National Electrical Code sets out a method for calculating what that service is already committed to: the square footage, the fixed appliances, the range, the dryer, the HVAC equipment, and so on. Subtract the calculated load from the service size and what remains is available capacity.
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<br>A Level 2 charger is a continuous load, which means the circuit must be sized at 125 percent of the charger’s rating. A 48-amp charger needs a 60-amp circuit. That is a large piece of a 100-amp service.
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<br>Newer neighborhoods on the northwest side and out toward Maize tend to have 200-amp services as standard, and often plenty of headroom. Older housing in Riverside, College Hill, Delano and south Wichita frequently does not. The same charger that drops into one house in an afternoon is a service upgrade in the other.
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<br>The options when capacity is short
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<br>This is where the useful part of the conversation happens, because the answer is rarely just “upgrade the service.”
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<br>Lower the charger’s rating. Most Level 2 units are adjustable during commissioning. A 32-amp setting on a 40-amp circuit adds roughly 25 miles of range per hour of charging. For a household driving 40 miles a day, that is a full recharge in under two hours overnight. The 48-amp setting solves a problem most drivers do not have.
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<br>Use a load management device. These monitor total service draw and throttle or pause the charger when the house demand rises. Several manufacturers make them and the code recognizes the approach. It is often dramatically cheaper than a service upgrade.
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<br>Feed from the meter with a service-rated splitter. Certain listed devices allow an EV circuit to be taken ahead of the panel with built-in load management.
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<br>Upgrade the service. Sometimes this is genuinely the right call, particularly if the panel is full, the main is 100 amps, and other work is planned anyway.
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<br>Permits and inspection
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<br>EV charger circuits in Wichita and Sedgwick County are permitted through the Metro Area Building and Construction Department and inspected against the 2023 National Electrical Code, which the county adopted effective January 1, 2025. That code cycle brought specific requirements around EV supply equipment, including GFCI protection provisions and rules on disconnecting means.
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<br>Addresses in Andover permit through the City of Andover rather than MABCD, since Andover sits in Butler County. It is a distinction worth confirming before the work starts, because a permit pulled with the wrong authority is not a permit.
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<br>Kansas has no statewide electrician license. The licensing is local, issued through MABCD for the Wichita metro.
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<br>The garage details that get overlooked
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<br>Where the charger mounts matters more than people expect. Cord lengths are fixed, cars park in a particular orientation, and the charge port is on a different corner depending on the manufacturer. Measure with the car in the garage before anyone drills.
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<br>Detached garages introduce a separate question. If the existing feed to the garage is a small subpanel on a 30 or 50 amp feeder, the charger may exceed it. Upsizing a buried feeder is trenching work and it changes the cost picture entirely.
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<br>Outdoor installations need equipment rated for the location and mounted at a height that keeps the connector out of standing water and snow.
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<br>The sequence that saves money
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<br>Get the load calculation before buying the charger, not after. It takes about an hour, and having Wichita electrical services run it tells you which charger to buy rather than which compromises to make around one you already own.
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<br>If a panel upgrade is likely in the next few years for other reasons, do it before the charger install rather than after. Running the circuit twice costs more than running it once.
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<br>The utility side
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<br>Some utilities offer off-peak rates for vehicle charging, and some offer
rebates toward the equipment or the installation.
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<br>Whether that applies is worth checking before the install rather than after,
because certain programs require a separate meter or a specific communicating
charger, and retrofitting either is more expensive than specifying it at the
start.
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<br>The same call answers whether the transformer serving your street has capacity
for the added load, which in older neighborhoods with several EVs on one
transformer is occasionally a real constraint rather than a formality.
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