881-4027.9 * INSTALLATION AND OPERATING INSTRUCTIONS 8BT2 * Revision 04
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Fig3. Rating plate of the panel
2.1.9. IAC Classification
The data (pos.nr.
in fig3) describes the internal arc classification of the panel
according to IEC 62271-200. The entries IAC A FL 25 kA 1 s in the example shown
mean:
• IAC: Internal Arc Classification
• A: Type of accessibility A; for authorized personnel only; switchgear in closed
electrical service location; access for expert personnel only.
• F: Internal arc classification for the front side (Front)
• L: Internal arc classification for the lateral sides (Lateral)
• R: Internal arc classification for the rear side (Rear)
• 25 kA: Tested short-circuit current
• 1 s: Rated duration of short circuit
2.1.10. X-ray regulations
The vacuum interrupters fitted in the 3AH vacuum circuit breakers are type-approved in
accordance with theX-ray regulations of the Federal Republic of Germany. They conform to
the requirements of the X-ray regulations of January 8, 1987 (Federal Law Gazette (BGBI.)
I Page 144) §8 and Annex III Section 5 up to rated short-duration power-frequency voltage
(rated power-frequency withstand voltage) stipulated in accordance with IEC/DIN VDE.
2.1.11. Operating conditions
8BT2 switchgear is designed for normal indoor operating conditions according to IEC 62271-1.
In this respect, the following limit values for the ambient air temperature must be complied
with as a minimum:
The ambient air temperature
Maximum value
+40
Minimum value
-5
Maximum value of 24-hour mean
+35
When 8BT2 switchgear is used in regions with high air humidity or considerable
temperature fluctuations, there is risk of condensation. The formation of condensation
should be an exception under normal operating conditions. To prevent condensation,
rusting or other serious consequences, the associated preventive measures must be taken
by installing electrical heating equipment in the switchgear. The ambient air must not be
significantly polluted by dust, smoke, corrosive and/or flammable gases, vapors or salt.
In the normal service condition, the site altitude shouldn’t exceed 1000m above sea level
according to IEC 62271-1:2007, clause 2.1.1. If it exceeds 1000m value, Ka correction factor
should be considered as explained below:
