Operating manual HVL 120-0.3
1 GENERAL
This document is applicable to the ABB low voltage limiter, type HVL 120-0.3
The data in this operating manual describes the product, but does not establish the right to a guarantee
claim. In the interest of our customers, we continually strive to improve our products and adapt them to the
latest technological standards. Consequently, it is possible that small differences may occur between the
supplied product and the product description or the operating manual.
This document was written for
qualified service personnel
working in the field of railway engineering
technology. All safety regulations of the railway operator and the national safety authorities must be
observed and complied with, and only qualified and instructed personnel who have the required experience
of safety practices may install and maintain these devices. This manual does not in any way replace the
required training and experience with regard to safety regulations. Precautionary measures and warnings
must be strictly followed where there is a danger to persons or where the installation may be damaged.
The information contained here is intended to ensure that this product is installed correctly. As in all work
situations, ABB has no control over the conditions present in the electrical network of the railway operator,
which can have a marked effect on the installation of the product. It remains the responsibility of the product
user to choose the most suitable methods of installation. ABB accepts no liability for direct or indirect
damage arising from the use or misuse of this product.
2 DESCRIPTION AND FUNCTION
Stationary installations for the supply of railway traction current employ the rails, amongst other means, as
the return path for the traction current. In the case of DC current railways, electrically conductive parts or
structures located in the area of the overhead line and the current collector are not simultaneously
connected to the return current path and the earth potential. This simultaneous connection is not allowed to
be of long duration, owing to the stray current diffusion in the ground and the associated effects. Electrically
conductive parts that are not connected to the earth potential can become live with unacceptable shock-
hazard voltages.
The low voltage limiter HVL 120-0.3 is used in the case of DC current railways, to provide effective
protection for personnel and equipment. It fulfils the tasks of a voltage limiting device in accordance with EN
50122-1, and limits the occurring shock-hazard voltages to safe values. The resulting values are distinctly
below the limit values defined for these voltages in the EN 50122-1 standard.
An important benefit of the low voltage limiter is its resetting capability under certain operating conditions.
Tests must be carried out to establish whether the requirements for the protection of personnel and
equipment can still be guaranteed, not just in the case of new structures, but also where structural
modifications are made to existing systems. If these requirements are no longer fulfilled, the use of the low
voltage limiter HVL 120-0.3 should be examined.
1HC0023892 AA
EN
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