ABB VD4 Series Instruction Manual - page 42
42 VD4 Vacuum-circuit-breaker | Instruction manual 534/01
9
Application of the X-ray regulations
One of the physical properties of vacuum insulation is the
possibility of X-ray emissions when the contact gap is open.
The specified test performed by the Physikalisch-Technische
Bundesanstalt (PTB) in Braunschweig demonstrates that the
local dosage output of 1 µSv/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 withstand 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 stan-
dards 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.