Odd Language #132: Off Off

I recently wrote a USENET post in which I stated: “The trolley buses in Vancouver had — probably still do have — batteries and could operate off the wires and off the batteries for a short time, respectively.”

The issue: As I continued, ‘That is, “off” as in “not on” and “off” as in “from”.’ “off” is being used for not using the wires and for using the batteries.