In TN systems, the star point of the feeding transformers is connected to earth through a low impedance and the exposed conductive parts of the electrical installation are connected to the protective earth (PE) of the system. In TT systems, the star point is also connected to earth through a low impedance but the exposed conductive parts of the electrical installation are earthed independently from the system earthing.
In TT systems, one point is connected directly to ground (functional grounding). The exposed-conductive parts of the electrical installation are connected to ground electrodes which are electrically isolated from the ground electrode for grounding the system.
Permissible protective devices:
Name | Category | Size | Language | Timestamp | D-/B-Number |
---|---|---|---|---|---|
Product Overview - Residual Current Monitoring | Product Overviews | 6.2 MB | EN | 2023/11/0909.11.2023 | |
Making Gains in Safety - NürnbergMesse Relies on the Monitoring Devices from Bender | Technical Article | 276.7 KB | EN | 2019/05/1313.05.2019 |
Products
Four-channel DC, AC and pulse current sensitive residual current monitor for earthed AC, AC/DC and DC systems
Multi-channel AC/DC ground-fault monitor
Four-channel DC, AC and pulse current sensitive residual current monitor for earthed AC, AC/DC and DC systems
Multi-channel AC/DC ground-fault monitor