I am installing a garage door opener. I am wiring this device in permanently from an existing junction box. When I hook up the unit black to black and white to white and grounded. The circuit breaker will not go on. I have checked the wiring and everthing should be ok. The circuit is a GFI Ground fault interrupt circuit. Is there a trick of the trade here. When I disconnect the opener from the junction box. The circuit is fine. All light fixtures work perfectly.