Adjustable EVSE
If the calculated load and demonstrated load don’t allow enough available capacity for your proposed EVSE, maybe you could use an EVSE set to a lower current (amp) rating. Many people don’t actually need to charge at 40A or 48A, but would do fine with 16A, 24A, or 32A, for example. Some EVSEs that come with higher ratings can be adjusted (derated) to a lower maximum current in ways that meet approval for inspections.
Interpretations may vary by AHJ (Authority Having Jurisdiction) or Province; this information is based on Ontario (ESA) and BC (Technical Safety BC)
The general requirements are that the EVSE is:
Fixed-in-place - a mounting means for EVSE that requires a tool to remove
the EVSE from its mounted position.
Restricted access to the adjusting means, such as requiring a tool to access or a unique password.
Permanently marked with warning label not to adjust the maximum current and include:
- Maximum charging current
- Installed breaker or fuse size
- Installed conductor size
Additional Information/References
For Ontario (ESA bulletins)
https://esasafe.com/assets/files/esasafe/pdf/Electrical_Safety_Products/Bulletins/86-01-7.pdf
- Section 4) for adjustable EVSE
For British Columbia (TSBC)
- See adjustable field settings under "Markings"