We have 5 double outlets connected on one circuit. Now we noticed that if we connect outlet tester to any outlet it's indicate 'correct', but if we plug appliance to any one of outlets in the circuit, the tester starts to shoe 'open ground'. It happens with every outlet that we tested and any outlet we connected appliances to.
We checked the tester with other outlets in the house and it works fine.
We already tried to open all the outlets and tighten the wires.
Does anyone have any ideas on what's going on?
Thanks