EnerGene said:
I built an OpenEVSE Kit - Level1 & Level2 50A.
What do I need to do to charge on a TT-30 at 20A?
Normally you would keep your OPENEVSE at "auto" for L1/L2 selection.
In the standard software that comes with the OPENEVSE this is defined:
// maximum allowable current in amps
#define MAX_CURRENT_CAPACITY_L1 16 // J1772 Max for L1 on a 20A circuit
#define MAX_CURRENT_CAPACITY_L2 80 // J1772 Max for L2
So if you want to take advantage of the amps available at the TT(travel trailer)30
there are 2 things you can do:
1) alter the (opensource firmware)
This is imo the best solution
Change the line in open_evse.h from
#define MAX_CURRENT_CAPACITY_L1 16 // J1772 Max for L1 on a 20A circuit
to
#define MAX_CURRENT_CAPACITY_L1 24 // Max for L1 on a TT 30A circuit
compile the software, upload it to the openevse cpu
From then on, you can increment L1 charging in increments of 2 Amps up to 24 amps.
2) alternative without programming
manually select L2 charging (instead of auto detect L1/L2)
That way you also will be able to select 20 amps, but the counting of kWh will be off since it will calculate with 240 volts instead of the real 120 volt.
If you want, I can compile a firmware image with the extra amps setting and upload it somewhere.
You would need a programmer like
https://store.openevse.com/collections/frontpage/products/openevse-programmer (or one from ebay) to upload the new firmware to the openevse.
