How to install Stetzerizer netfilters – Important!

To drastically reduce the level of dirty electricity, follow the following procedure:

Step 1: Measure the level of dirty electricity

With the so-called Stetzerizer microsurge meter you can determine the degree of contamination and install the correct amount of netfilters in the right place.

The Stetzerizer microsurge meter displays the values in GS units.

Stetzerizer microsurge meter

Step 2: Install netfilters

For the best result: switch all electronic devices – especially televisions and computers – ON during the installation of the netfilters.

Install 1 Stetzerizer netfilter in a socket near every television and computer. After installing netfilters there this will also lower the level of dirty electricity in the rest of the house.

Continue your measurement with the socket in the electricity distribution board. This because the electricity supply in your house is the same as the one of your neighbour. So if they cause electromagnetic pollution, this may also pollute your electricity network.

If the readings on the microsurge meter are higher than 50 GS units, plug in one or more Stetzerizer netfilters in a socket nearby the electricity distribution board.

After installing a netfilter you should measure again. If the readings are at least 20% lower than the reading without a netfilter, then you should leave the netfilter in the socket.

Measure the readings of the next socket and repeat the process.

When a filter is overloaded you may hear a zoom. Remove the netfilter or place an extra netfilter and measure again. Overloaded netfilters have to be avoided at all times.

Measure all sockets in the house and switch the radiation sources on and off. If the readings on the microsurge meter increase considerably when using a device it is recommended to use a netfilter if the device is used frequently.

Install the netfilters as close as possible to the device that causes the pollution.

Because nowadays we have many polluting sources in our homes it is very likely that several netfilters have to be installed. The average number of netfilters per house is 15. If not enough netfilters are installed it is likely that the netfilters will be overloaded and that has to be avoided at all times.

If you need assistance to install the netfilters please contact an expert of Shielding Technologies.

After installing the filters you should measure frequently in order to verify whether the readings have changed.

Remark 1: do the measurement in the kitchen after you have measured in all other rooms. This because normally there are few sockets in the kitchen. So it can be inconvenient to install a netfilter in the sockets in the kitchen.

Remark 2: if a Stetzerizer netfilter has to be installed in a socket that can be switched off, at the moment of installing the netfilter the socket has to be switched on.

Remark 3: It is not recommended to reconnect a Stetzerizer netfilter that is plugged into an electrical outlet and to which an electrical appliance is connected without first unplugging the electrical appliance from the netfilter. After unplugging the electrical appliance from the netfilter, plug the netfilter back into the socket, after which the plug of the electrical appliance can be reconnected to the netfilter.

After measuring the whole house and after the netfilters have been installed we advise to measure all sockets again. A maximum value of 50 GS-units is recommended and 35 GS-units or less is ideal.


After plugging in a netfilter in a socket you must NEVER plug in another netfilter in that netfilter.

After plugging in a netfilter in a socket you must NEVER connect a device with a high ampere heating element (Like for example heaters, toaster ovens, electric griddles, roasting pans, etc.).