This article deals with the NEC 625.43, which spells out when a disconnect should be required at an installation site.  It says:

"NEC 625.43 Disconnecting Means. For equipment rated more than 60 amperes or more than 150 volts to ground, the disconnecting means shall be provided and installed in a readily accessible location. The disconnecting means shall be lockable open in accordance with 110.25"

So, what does this apply to?

This applies to our ZEFNET-80 (15.4kW) or ZEFNET-100 (19.2kW) units, when the chargers are sitting on 80A+ breakers, with the rated output of the charger being 64 Amps and upwards.  If a breaker panel is within line of site of the charger, this can often be considered as a readily accessible location, and therefore the breaker considered as being the disconnection means.

What does it NOT apply to?
Any of our units 11.5kW and below (ZEFNET-40/50/60) do not need seperate disconnection means in the 2017 NEC.

For ultimate clarity: check with your AHJ!