53
9
Application of the X-ray regulations
One of the physical properties of vacuum insulation
is the possibility of X-ray emissions when the con-
tact gap is open. The specified test performed by
the Physikalisch-Technische Bundesanstalt (PTB)
in Braunschweig demonstrates that the local dos-
age output of 1
µ
Sv/h at a distance of 10 cm from
the touchable surface is not exceeded when the
rated voltage is applied.
The results are as follows:
• Testing of the switching device or the vacuum
interrupter to VDE 0671 part 100 or IEC 62271-
100 at the relevant rated power frequency
withstand voltage may only be performed by
trained personnel observing the stipulations of the
EU basic standard (Stipulation 96/29/Euratom
of the senate from 13 May 1996 (ABI.L 159 from
29 June 1996)).
• Application of the rated power frequency with-
stand voltage specified for the switching device
by VDE 0671 part 100 or IEC 62271-100 is
completely safe.
• Higher voltages than the rated power frequency
withstand voltage or DC test voltage specified in
VDE or IEC standards must not be applied!
• The containment of the above mentioned local
dosage output with the vacuum interrupter in the
open position is dependent on maintenance of
the specified distance between the contacts
(which is automatically ensured with correct
mechanism function and force transmission).
• Safety clearances must be maintained.
