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M-LB-(Ex-)2000-System – Surge Protection Barriers
Product Specifications
2.2.1
Surge Protection Barriers for Grounded Signal Lines
Surge protection barriers for grounded signal lines provide a defined protection level from line
to earth by connecting the signal lines to earth via suppressor diodes.
Use this surge protection barrier if the apparatus to be protected is not isolated from earth,
e. g., in the case of applications in a non-hazardous area or for applications with zener barriers,
Figure 2.4
Example of a surge protection barrier for grounded signal lines
2.2.2
Surge Protection Barriers for Not Grounded Signal Lines
Surge protection barriers for not grounded signal lines are connected with earth
via a gas discharge tube only. This results in a greater insulation voltage from line to earth.
Use these surge protection barriers if the device to be protected is operated in an unearthed
signal loop. Typical applications for this device are galvanically isolated signal loops,
which can be found after isolated barriers or signal conditioners, see Figure 2.2
The breakdown voltage of the gas discharge tube is less than 500 V AC from line to earth.
Observe the breakdown voltage for insulation tests.
Figure 2.5
Example of a surge protection barrier for not grounded signal lines
M-LB-2144
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M-LB-2142
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