[trionyx]

Dear Forum members,
I have bought a used RPM meter.
The RPM meter contains 3 cable. One is red for plus, the second is black for minus, and the green should be connected somewhere, maybe transformer? Could you please tell me exactly where, maybe some picture of it.. From where can I get also the power to maintain it. I mean to which point should I make the connections (if possible to keep the wire length at minimum)
Thanks!