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If the indicator window on the SPD turns red

What does it mean that the indicator window on the SPD changes from green to red?

In order to ensure the safe operation of the Surge protection device, according to international standards, the pressure-limiting Surge protection device must be configured with an external disconnector or an internal disconnector in structure, and has a state indicator of the disconnector.

The status indicator of the disconnector is represented by the color of the window on the Surge protection device. When the disconnector works normally, the window turns green; when the Surge protection device fails, the disconnector acts and the window turns red. The main console issues an alert for the failure of the Surge protection device.

There are 3 things that cause the green window of an SPD to turn red:

1 The varistor of the functional element of the voltage-limiting SPD is aging, the leakage current is too large, the element is heated, the thermal protection disconnector is disconnected, and the window turns red;

2 The selected value of Uc of the SPD is lower than the actual working voltage of the site, including the large interference voltage of the site for a long time, which causes the varistor of the functional element of the SPD to be in the continuous conduction process, the temperature of the element is too high, and the heat The protective disconnector is disconnected, and the window turns red;

3. The welding quality of the contacts of the disconnector is poor. During the transportation and installation of the SPD, the contacts are cracked and disconnected due to the external force of vibration or the stress of the environmental temperature change during use.

Based on the above three reasons, it can be concluded that:

1. The Surge protection device will heat up and separate the disconnector due to the aging of the internal components due to its long service life, and a new SPD module needs to be replaced.

2. It is very important to select the Surge protection device with the correct parameters. If the SPD works in a power system that does not conform to the actual situation due to the wrong selection of the SPD parameters, it will accelerate the thermal separation of the SPD and cause the SPD to fail. Even if the main console receives the remote signal output status change, and the on-site personnel replaces the SPD module, if the replaced SPD module still has the original parameters, the use time will still not be long. Therefore, it is very important to choose the SPD with the correct parameters. How to choose the correct SPD can be clicked here: How to choose the SPDs or contact us, our professional team will analyze what parameters of the surge protector should be equipped in different site environments .

3. The poor production process of the Surge protection device and the use of cheap solder raw materials are one of the reasons for the disengager to turn red. Due to poor production process and poor quality of solder raw materials, SPD cannot withstand the stress of external vibration during transportation and installation and the stress of ambient temperature changes during use. It is easy to cause the separation of the disconnector and cause the indicator window to turn red.

THOR SPD soldering process adopts mechanical automation soldering process and high-quality soldering tin materials throughout the whole process to ensure that each SPD is delivered to every customer in a 100% state.

Summary: The green window on the Surge protection device turns red, providing a direct signal to the staff at the SPD installation site, indicating that the Surge protection device has lost its lightning protection function and is separated from the protected device. Therefore, the module with the red window must be replaced immediately.