18
N.
N.
Caption
N.
Number if closing-opening cycles allowed for the vacuum interrupters.
Ia
Breaking capacity of the vacuum interrupters.
Fig. 7a
Fig. 7b
7. Installation
7.1. General
Correct installation is of primary importance. The manu-
facturer’s instructions must be carefully studied and fol-
lowed. It is good practice to use gloves for handling the
pieces during installation.
All operations regarding installation, putting into service,
service and maintenance must be carried out by qualified
personnel.
7.2. Installation and operating conditions
The following Standards must be taken into particular consideration
during installation and service:
– IEC60694/DIN VDE 0101
– VDE 0105: Electrical installation service
– DIN VDE 0141: Earthing systems for installations with rated voltage
above 1 kV
– All the accident prevention regulations in force in the relative coun-
tries.
7.2.1. Normal conditions
Follow the recommendations in the IEC 60694 and 62271-100 Stand-
ards. In more detail:
Ambient temperature
Maximum
+ 40 °C
Average maximum over 24 hours
+ 35 °C
Minimum (according to class– 5),
apparatus for indoor installation
– 5°
Humidity
The average value of the relative humidity, measured for a period longer than 24
hours, must not exceed 95%.
The average value of the pressure of the water vapour, measured for a period longer
than 24 hours, must not exceed 2,2 kPa.
The average value of the relative humidity, measured for a period longer than 1
month, must not exceed 90%.
The average value of the pressure of the water vapour, measured for a period longer
than 1 month, must not exceed 1,8 kPa.
Altitude
< 1000 m above sea level.
7.2.2. Special conditions
Installations over 1000 m a.s.l.
Possibile entro i limiti consentiti dalla riduzione della rigidità dielettrica dell’aria.
Increase in the ambient temperature
Reduction in the rated current.
Encourage heat dissipation with appropriate additional ventilation.
Climate
To avoid the risk of corrosion or other damage in areas:
– with a high level of humidity, and/or
– with rapid and big temperature variations, take appropriate steps (for example, by
using suitable electric heaters) to prevent condensation phenomena.
For special installation requirements or other operating
conditions, please contact ABB.
The areas involved by the passage of power conductors
or auxiliary circuit conductors must be protected against
access of any animals which might cause damage or dis-
services.
7.2.3. Trip curves
The following graphs show the number of closing-opening cycles (N.)
allowed, of the vacuum interrupters, according to the breaking capacity
(Ia).