David108108
Electrical
- Jul 25, 2024
- 23
Hi everyone,
I'm a newbie here, and this is my first post. Thanks for taking the time to read through it.
I have a client who recently used an EMI Power Line Monitor to measure noise on their mains supply. This device can be plugged into any socket around the house to detect noise. Here’s a brief description of the monitor:
Product Description:
The Line EMI Meter measures electromagnetic interference (EMI) in a single-phase AC power line. It plugs into a wall outlet and does not require a battery. The device immediately displays total line noise in millivolts peak to peak (ranging from 1999.9 mVp-p with a resolution of 0.1 mVp-p) within the frequency range of 10 KHz to 10 MHz (where sensitivity is half of the maximum sensitivity). It also has a speaker that plays the sound of the EMI, amplitude demodulated, which helps identify the source of the interference (e.g., AM or shortwave radio stations, motors, or electric arcs).
A good reading on this meter would be around 400 mV, but my client was getting a consistent reading of 1400 mV, indicating a significant increase in noise. I asked if there had been any recent changes in the house or nearby. Here’s what he mentioned:
The neighbor on the left installed solar panels.
The neighbor on the right installed a garden WiFi booster.
There were recent works carried out on his street.
His detached house has a TT earthing arrangement. Here’s my preliminary diagnosis:
There could be DC transient voltage from the neighbor’s solar panel inverter, possibly causing DC leakage to ground.
The WiFi booster from the neighbor on the right might be causing interference.
The street works might have introduced more noise into the incoming mains supply.
The EMI monitor registered the strongest noise level when plugged into a kitchen socket, but high readings were also observed in various other parts of the house. This likely rules out a faulty circuit.
I would greatly appreciate any input or advice to assist my client in resolving this issue.
Thank you!