Siemens TYPE VBII Series Application Manual page 4

General and Heavy Duty Features
Siemens Type VBII Safety Switch
Application
General Duty Switches
General Duty Switches are intended for
applications where reliable performance
and continuity of service are needed,
but where duty requirements are not
severe and usual service conditions
prevail. These switches are intended for
use primarily with supply circuits rated
240V AC or less where the available
fault current is less than 100,000A
when used with Class R or T fuses
or 10,000A max. when used with
Class H fuses.
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Application
Heavy Duty Switches
Heavy Duty Switches are intended for
use in applications where:
1. Rugged construction, reliable
performance, continuity of service and
ease of maintenance are emphasized
2. Available fault currents higher than
10,000A are likely to be encountered,
such as in manufacturing plants, mass
production industries and commercial,
institutional and other large buildings
served by network systems or
transformers of higher capacities
3. System voltage is 600V AC or DC
max
4. A Type 12 or 4 / 4X enclosure is
required
Short-circuit Withstand Ratings
General Duty Switches
Suitable for use on systems capable of
delivering not more than 100,000 RMS
symmetrical amperes of fault current
when Class R fuses are installed. Also
rated 100,000 AC max. in 200-600A
ratings with Class J and T fuses.
Short Circuit Withstand Ratings
Heavy Duty Switches
Suitable for use on systems capable of
delivering not more than 200,000
➀
RMS symmetrical amperes of fault
current when Class J or R fuses are
installed except the 800 and 1200A
switches, which are suitable for use on
circuits capable of delivering not more
than 200,000 RMS symmetrical
amperes of fault current when
Class L fuses are installed. 100-1200A
switches with Class T fuses and field
adapter kit are also 200,000 RMS
symmetrical rated.
➀ 100,000 RMS for 60 A compact non-fusible switches.
Fuses
General Duty Switches
Fusible switches will accept
the following UL class fuses:
Class H
Class K
Class R—Class R fuse clip rejecter kits
are required.
Class T—200-600A switches (200A
switches require field adapter kit)
Heavy Duty Switches
Fusible switches will accept
the following UL class fuses:
Class H
Class K
Class R—Class R fuse clip
rejecter kits are required
Class J—240 and 600V switches 600V
switches are field convertible
Class L—800 and 1200A switches only
Class T—100-1200A switches (100 and
200A switches require an adapter kit)
Cover Interlocks
General Duty Switches
Defeatable-cover interlocks on Type 1
switches and 60-600A Type 3R switches
prevent the switch door from being
opened when in the ON position.
Heavy Duty Switches
Defeatable dual cover interlocks are
standard on all heavy duty switches.
Prevents cover from being opened
when switch is in the ON position and
prevents switch from being turned ON
when door is opened.
Padlocks
General & Heavy Duty Switches
Padlockable cover latch and multiple
padlock provisions on handle.
NEMA Specifications
Meets NEMA standard KS-1-1990 for
type GD and HD switches.