I'm installing an outlet plate sealers in my home, so I turned off the circuit breaker for all the outlets. However, when I removed the plate cover, and used a Non-contact voltage tester, it detected voltage on the Live (Black) wire. I then used a Receptacle Tester and a phone charger to confirm there's no electricity in the outlet which there wasn't.
How did the voltage tester detect voltage in the live wire if the circuit breaker was off? Is this phantom voltage? Note that I've used the voltage tester on the 70v-1000v mode.
Note that I've checked the other answers in this question, and all the questions it links to. But I'm not sure which one applies to my case?