Opferanode isolierter Einbau

What is the insulated installation for?

The insulated installation of a magnesium anode makes it easier to assess whether the anode is still operational or whether it has already used up to such an extent that sufficient protective current can no longer flow. A visual inspection, which requires the system to be switched off and the protective anode to be removed, can be dispensed with. Instead, the flowing protective current is checked by measuring the insulated magnesium anode with an anode test or resistance meter.

Opferanode isoliert im Warmwasserspeicher

How does the insulated installation of the sacrificial anode work?

The electrically conducting contact between the magnesium anode and storage tank is separated with the help of insulation, for example in form of insulating covers. However, this is subsequently restored by connecting the sacrificial anode to the storage tank with an additional cable. The protective current can therefore flow again. The decisive factor is that a measuring device can be connected in between and thus the operational capability of the insulated sacrificial anode can be checked. Once the measurement is complete, the direct contact between the anode and the storage tank must be reestablished.


Isolierter Aufbau Opferanode




4:Insulating cover


6+9:Hexagon nut

7:Ring cable lug with cable

8:Lock washer


The insulated installation procedure is somewhat more complex in terms of preparation. However, the performance of the annual inspection of the anode recommended by us is enormously facilitated. The condition of the insulated sacrificial anode can be checked regularly and assessed on the basis of the measured values. 

  • > 0,3 mA: Anode is operational 
  • < 0,3 mA: Remove anode and continue with the visual inspection.

If required, we will deliver the anode fastening set including ground cable for the insulation installation free of charge. 

Disadvantages of an insulated installation:

It can easily happen, that the installation is not carried out properly. As a result, there is a risk that the anode will not work and the storage tank will rust through. In addition the measuring instruments can show imprecise values and therefore lead to a wrong conclusion.

How to measure the protective current in a storage tank

The storage tank must be filled with water for the protective current measurement. Please ensure that the protective terminals are in perfect contact. The connection terminals may only be connected to bare metal surfaces. Then the connecting cable, which connects the sacrificial anode with the storage tank, must be disconnected at one of the connection points. Now the protective current can be determined with a measuring device. After the measuring process is finished, do not forget to reconnect the ground cable to the storage tank. Otherwise, the magnesium anode will not work.

Schutzstrom messen Opferanode

Can I exchange an uninsulated anode for an insulated one?

We are asked this question almost daily by our numerous customers. In principle, this is possible, but you have to make structural changes to the storage tank. The ground cable must be connected to ground.

Reversed, an insulated magnesium anode can always be exchanged for a non-insulated anode. Many of our customers are somewhat uncertain whether the magnesium anode will work without insulation. The uninsulated magnesium anode works always, the contact between anode and storage tank is given via the thread at any time.

Perfect alternative: Our signal anode!

Alternatively, if you want to keep an eye on the condition of your anode but save as much time  and effort as possible, you can purchase a signal anode from our online store. Signal anodes indicate on their own when they are used up.


Insulated installation has many advantages, but can have the exact opposite effect, if not handled properly. It's no problem to exchange an insulated anode with an uninsulated one. A magnesium anode that is not insulated will always work. The contact to the storage tank via the thread is given at all times.

Click here for sacrificial anodes or chain anodes for the insulated installation.