Your panel size is the starting point of the choice, not the answer. A 200 A panel does not automatically clear a 48 A charger, and a 100 A panel does not automatically rule one out: a licensed electrician’s load calculation under the National Electrical Code decides what your home can spare, and the charger is then chosen — or set — to fit that number. Panel size changes which outcome is likely, and how much flexibility to buy in the charger.
Key Takeaways
- Panel size sets the likelihood of each outcome; the NEC load calculation sets the actual limit.
- Charging counts at 125% in the calculation: 32 A reserves 40 A, 48 A reserves 60 A.
- On a tight result, an adjustable charger set to the headroom is the honest fit.
- Empty slots are not capacity; ask the three questions before ordering.
Why the Calculation, Not the Panel Label, Decides
EV charging is a continuous load, so the NEC counts it at 125%: a 32 A charger reserves 40 A in the calculation, a 40 A charger reserves 50 A, and a 48 A charger reserves 60 A. The electrician totals your home’s existing calculated load — heating, cooking, water heating, laundry, cooling — then adds the charger’s reservation. That figure is standardised and conservative, not your meter’s real peak; empty breaker slots show space, not capacity. Our guide to panel capacity and charger size explains the method; what follows is the product choice.
The Three Panel Sizes as Starting Points
| Panel | Starting expectation — not a guarantee | Charger shape that fits the conversation |
|---|---|---|
| 100 A | Headroom is the open question; a reduced charging current is a common outcome | An adjustable unit, set to whatever continuous current the calculation leaves |
| 150 A | The middle case: many homes clear a mid-size EV circuit, but the existing loads still write the answer | An adjustable portable or a wallbox sized to the calculated result |
| 200 A | The widest headroom; a full 48 A installation is a realistic candidate — still calculated, never assumed | The full range, including the 48 A wallbox on a 60 A breaker if the sum allows |
Read the middle column as likelihoods, not permissions. An all-electric 200 A home can total higher than a light 150 A home with gas appliances — the same charger can fit one 200 A house outright and need a step-down in another.
The Adjustable Answer
When the calculation leaves less than a full-size circuit, the honest product answer is a charger whose current can be set to the headroom. The EV-ACS3210T adjusts in six steps from 10 A to 32 A; the EV-ACS4005T adjusts at 16 / 24 / 32 / 40 A up to 9.6 kW. The electrician applies the 125% rule to the chosen setting — a unit set to 24 A is calculated as a 30 A load — and the setting can be revisited if the home’s loads change. A fixed-rate unit such as the EV-AC04001U at 9.6 kW has no such dial: it fits only homes whose calculation clears its full reservation. If it leaves too little for any useful setting, an electrician may propose load management equipment or a service upgrade; no EVDANCE charger here claims built-in load management, so treat that as electrical work, not a product feature.
Choosing From the EVDANCE Range by Panel Result
Once the calculation exists, the choice is short. If it clears 60 A of reservation, the EV-ACT5006T wallbox at 48 A and 11.5 kW is the full-size option. If it clears less, an adjustable portable is set to the number that fits. If it clears nothing usable, the electrical work comes first. Bring the electrician three questions:
- What is my home’s calculated load today, before the charger?
- How much continuous EV current fits, and what breaker does the 125% rule pair with it?
- Does the answer change if a heat pump, a second EV or an electric range arrives later?
The method and the breaker pairings are covered in our load calculation basics and breaker sizing guides.
Frequently Asked Questions
I have a 100 A panel. What is the honest answer?
Often home charging at a reduced setting, sometimes electrical work first. Many 100 A homes charge well on an adjustable unit set below its maximum; the exact setting comes from your load calculation, not the panel label.
Does a 200 A panel guarantee a 48 A charger?
No — the calculation decides, and a heavily loaded all-electric 200 A home can leave less room than a light 150 A one. The bigger service only makes the full-size outcome more likely.
Who runs the load calculation?
A licensed electrician, using the NEC method. It is their document — it supports the permit, and they carry responsibility for the result. Treat your own estimates as planning only.
Related Reading
- What Size EV Charger Can I Have at Home? Panel Capacity Explained
- Adding EV Chargers to a Building: Load Calculation Basics
- What Size Breaker Do I Need for an EV Charger?
- How Many Amps Does an EV Charger Need?
