My 3 ton Frigidaire outside compressor unit is running and cooling but from time to time makes a loud clicking sound and my inside lights dim. Is it safe to run the unit until the repairman gets here next week?

Have you been outside when this happens? Does it sound like it is coming from the compressor, or the fan?

In the back of the unit where the control box is located. The compressor is running when the clicking takes place. It will click and then a few minutes later will click again, all while the compressor is running and cooling the house. I turned it off overnight and then ran it this morning and it is doing the same thing. It is running now and has not clicked for 30 minutes or so and seems to do it when it only when the thermostat turns the unit on.