Warning to EV-1 Drivers

["Mander, Art" <amander@tristategt.org>]

A few days ago Don and Otmar mentioned damage to 120/240 volt chargers from
miswired neutrals.  This can only happen at a miswired three-phase delta
service.  When the customer has a mix of three-phase 240VAC and single-phase
120VAC loads, the utility will install a delta 240VAC bank with
neutral/ground at the midpoint of one side of the delta.  The adjacent
phases yield 120VAC to neutral, the third phase yields 208VAC to neutral
(120 X sqrt 3)  The third phase is known as the "wild" or "stinger" phase
and per code must be marked as such and must not be used for single-phase
loads.  That's why there are codes, inspectors, and qualified electricians.
Otmar and Don are trying to be good EV neighbors, but have miswired systems.

Art Mander, Denver