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Earth Monitoring System

For the protection to work properly, the correct status of the earthing system in an electrical installation is essential .


Would you like to know what % of your installed surge protection is actually providing effective protection?

TERRA® is the first protection device on the market that, in addition to indicating that it is properly wired, guarantees that there is an adequate path to earth, which is essential if the protection device is to shunt the energy peaks to earth effectively.


  • TERRA®’s simple information makes it the ideal ally for both unskilled personnel and maintenance professionals specialised in earth connections.
  • Helps avoid situations that might cause power cuts, repair costs, with the resultant damage to your brand image.
  • Provides additional information about the earthing system, with potential synergies for protection and safety in general, not just for surge protection.


1. Confirmation of proper installation

Almost 25 years of experience in the sector confirm that it is relatively common for wiring errors to occur during the installation of surge protection devices. These errors result in the loss of protection or risks to the installation itself.


2. Effective surge protection

Even when equipped with surge protection devices, the electrical installation may still be subject to the effects of overvoltage if the earth connection is inadequate or in poor condition.


3. Safety information in the event of indirect contact

Just as happens with surge protection devices, the safety of the electrical installation in the event of indirect contact is based on there being an earthing connection.

The importance of the earth connection
Surge protection devices discharge excess energy to earth, thus limiting the peak voltage to a value acceptable for the electrical equipment connected.
An earth in proper conditions is therefore an aspect not to overlook when it comes to effective surge protection. Continuously monitoring the state of the earth connection ensures proper operation of surge protection devices.


Surge-Trap TERRA