Today we would like to inform you about our latest thing in the Solar Monitor Modular System. We have developed additional piggy-back boards for a galvanic isolation of RS485 bus - 485 isolator.

485 isolator provides galvanic isolation between RS485 line voltage and SM2-MU voltage. Using 485 isolator as a protection against ground loops is appropriate especially on places where higher voltage than the voltage in the unit can appear in the bus due to its length. It also works as a Solar Monitor protection against electrostatic discharges and overvoltage up to 3 kV.

What galvanic isolation stands for?

The bus RS485 can be as long as 1,200 m. In such a case, devices on both sides of this bus are powered from sources, when further source is connected by a cable which has a certain resistance and when the current goes through this cable, there appears a potential on the ground cable as well. Therefore both sources do not have the same potential of their grounds. That's why any voltage towards these sources is different to each other, therefore the voltages on both ends of the RS485 bus are different. In the case the difference is too big the receiver may not react to sent data, in a worst case scenario it can be irreversibly damaged.

This can be prevented by optically isolating the device on one side of the bus. The light can reliably solve the potential differences, furthermore the optoparts also provide an electric strength with breakdown voltage of several kV(s) and therefore a protection against ESD or other low energy transient effects.

How to order?

Would you like to have 485 isolator in your Solar Monitor as well? You can already find it in our eshop.

2 options of 485 isolators are available, they only differ in their maximum communication speeds.

  • 485 isolator low speed (to 9600 Bd)

isolator low speed

  • 485 isolator (above 9600 Bd)

isolator high speed

If you order it together with a chosen SM2-MU model, we will install the isolator directly into it.

In case you have already got the Solar Monitor and you will just order the isolator, we will help you with its integration.

And you can then monitor with no fear.