I think the EVSE that is provided with the SR/F is an Aerovironment "Turbo Cord". The are available as straight 120 volts or 120/240 volts. The SR/F appears to have the latter. However, the unit is limited to 3 KW output so even though you have 6 KW of chargers, the Turbo Cord is going to limit you to no more than 3 KW input. And with the chargers not being 100% efficient, you will actually get somewhere around 2.5 to 2.7 KW DC into the battery pack. So charge times are going to be shorter if you got a EVSE capable of delivering around 30 amps. It won't use all of that but a 30 amp circuit is the minimum you would want to use. 30 amps at 240 volts can deliver 7.2 KW. However you can only use 80% of the circuit's output for a continuous load per code. This would put you at 5.8 KW.
You can figure your actual charge times if you know the state of charge of the battery. Even though the pack is rated at 14.4 KWH, usable is somewhat less. 13 KWH might be a more reasonable number. So if the battery is totally drained, for example you just need to divide the usable capacity of the battery by the DC charging KW available. In your case, with the Turbo Cord it would be 13/2.6=5. 5 is the number of hours it would take to complete the charge with your setup. If you had more input current and a bigger EVSE, the time would be cut in half. Those numbers are just guesses but should be close.
BTW--the owners manual states the nominal capacity of the power pack is 12.6 KWH so I was being generous.