Operating manual HVL 120-0.3
Before beginning the work, check the safety distance to adjacent live parts or
equipment. If there is a danger of inadvertent touching, the 5 safety rules for
establishing and securing the de-energised condition at the work location must be
carried out (see the section entitled Safety instructions).
Secure yourself against falling if the intended mounting position is on a mast or on a
high-level structure. For this purpose, use a secure working platform and wear your
personal protective equipment.
A low voltage limiter must not be removed from the electrical circuit until its operating condition has been
determined! For this, proceed as follows:
1. Measure the voltage via the connections of the HVL 120-0.3 with a measuring device suitable for DC
voltage.
2. Measure the current through the HVL 120-0.3 with a current probe suitable for DC current.
During
this operation, never disconnect a connection! Otherwise, there is the danger of an electric
shock.
3. If the voltage measurement gives a value greater than 50 V or the current measurement gives a
value greater than 0.3 A, then first of all the cause must be determined. If the cause is found and
rectified, the checks under Point 1. and Point 2. must be repeated.
4. The HVL 120-0.3 must be shorted out with a conductor of sufficient dimensions (observe the
national regulations and the requirements of the railway network operator). This conductor must be
arranged to ensure that detachment of the connection during removal of the HVL 120-0.3 cannot
occur.
5. Take a further measurement of the voltage via the connections of the HVL 120-0.3 with a measuring
device suitable for DC voltage. The voltage measurement should now give a value less than 1 V. If
this is the case, then the HVL 120-0.3 can be removed. Otherwise, the current circuit must be
checked again.
6. The volume resistance of the HVL 120-0.3 can now be measured with a standard Multimeter
3)
. The
resistance value obtained must be at least 1 k
Ω
. If this is not the case, then the HVL 120-0.3 is
defective and must be replaced. If the resistance value is equal to, or greater than 1 k
Ω
, it can be
concluded that the thyristors are functional, and the HVL 120-0.3 can be re-fitted.
7. The conductor used for shorting-out, must only be removed when the HVL 120-0.3 has been
completely re-fitted.
3)
For the resistance measurement, do not use an insulation resistance meter (Megger)! This could lead to a
false evaluation, since such measuring devices work at voltage levels which will cause the low voltage limiter
to change into its conductive state.
1HC0023892 AA
EN
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