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10. Application of the X-ray emission Standards
One of the physical properties of vacuum insulation is the possibility of
X-ray emission when the interrupter contacts are open.
The specific tests carried out at the PTB laboratories (Physikalisch-
Technische Bundesanstalt, in Brunswick - Germany) show that local
emission at a distance of 10 cm from the interrupter or pole surface,
does not exceed 1 mSv/h.
It follows that:
– at the rated service voltage the use of vacuum interrupters is abso-
lutely safe;
– application of the withstand voltage at power frequency, according to
the IEC 62271-100 and VDE 0670 Standards, is safe;
– application of a voltage higher than the withstand voltage at power
frequency or of a test voltage in direct current, specified in the IEC
and VDE Standards, cannot be used;
– limitation of the above-mentioned local phenomena, with interrupters
with open contacts, depends on keeping the specific distance be-
tween the contacts.
This condition is intrinsically guaranteed by correct operation of the
operating mechanism and by the adjustments of the transmission sys-
tem.
11. Spare parts and accessories
All assembly operations of spare parts/accessories must
be carried out following the instructions enclosed with
the spare parts, by ABB personnel or by suitably qualified
customer personnel with in-depth knowledge of the ap-
paratus (IEC 60694) and of all the Standards aimed at car-
rying out these interventions in safe conditions. Should
the maintenance be carried out by the customer’s person-
nel, responsibility for the interventions remains with the
customer. Before carrying out any operation, always make
sure that the circuit-breaker is open, the springs discharged
and that it is not energised (medium voltage circuit and
auxiliary circuits).
To order circuit-breaker spare parts/accessories, refer to the ordering
sales codes indicated in the technical catalogue and always state the
following:
– type of circuit-breaker
– rated voltage of the circuit-breaker
– rated normal current of the circuit-breaker
– breaking capacity of the circuit-breaker
– serial number of the circuit-breaker
– rated voltage of any electrical spare parts.
For availability and to order spare parts, please contact our Service
office.
11.1. List of spare parts
– Shunt opening release
– Additional shunt opening release
– Undervoltage release
– Contact for signalling undervoltage release energised/de-energised
– Time delay device for undervoltage release
– Mechanical override for undervoltage release
– Shunt closing release
– Spring charging geared motor with electrical signalling of springs
charged
– Geared motor thermomagnetic protection circuit-breaker
– Contact for signalling geared motor protection circuit-breaker open/
closed
– Contact for signalling closing springs charged/discharged
– Circuit-breaker auxiliary contacts
– Opening solenoid
– Key lock in open position
– Opening pushbutton protection
– Closing pushbutton protection
– Set of six main isolating contacts
– Current sensors
– PR521 protection releases
– Connector complete with sheath
– Wheel Kit
– Operation counter
– Complete pole.
