Description
Manufacturer | ABB |
Brand | ABB |
Series | module |
Part Number5SHY5055L0002 | 5SHY42L6500 |
Product Type | module |
Quality | 100% New Original |
Stock | In stock |
Delivery time | 1-3 days after Payment |
After-sales Service | Have |
Warranty | 1 year |
Shipping term | DHL / FEDEX/ EMS /UPS/TNT/EMS |
Packaging details: if you need an urgent delivery order, please feel free to contact us, and we will do our best to meet your needs.
Price problem: if you find that other suppliers offer cheaper prices for the same product, we are also willing to provide you with reference prices and give you further discounts.
TT or TN systems:
• if the cross section of the neutral conductor is the same or larger than the
cross section of the phase conductor, there is neither the need to detect
overcurrents on the neutral conductor nor to use a breaking device (neutral
conductor is not protected or disconnected); this requirement applies only if
there are no harmonics that may, at any instant, cause r.m.s. current values
on the neutral conductor higher than the maximum current detected on the
phase conductors;
• if the cross section of the neutral conductor is less than the cross section of
the phase conductor, overcurrents on the neutral conductor must be detected
so as to have the phase conductors, but not necessarily the neutral conductor,
disconnected (neutral conductor protected but not disconnected): in this case
the overcurrents on the neutral conductor do not need to be detected if the
following conditions are simultaneously fulfilled:
1.the neutral conductor is protected against short-circuit by
the protective device of the phase conductors;
2.the maximum current that can flow through the neutral
conductor during normal service is lower than the neutral
current carrying capacity.
In TN-S systems, the neutral need not be disconnected if the supply conditions
are such that the neutral conductor can be considered to be reliable at earth potential.
As already mentioned, in TN-C systems, the neutral conductor is also a
protective conductor and cannot therefore be disconnected. Furthermore, if
the neutral conductor is disconnected, the exposed conductive parts of the
single-phase equipment could take the system rated voltage to earth.
In certain specific cases, the neutral conductor has to be disconnected to
prevent currents circulating between parallel supply sources (see Figures 2 and 3)