M ED I U M VO LTAG E P R O D U C T S
3
1.1 General
The vacuum circuit breakers of type VM1-T are
intended for indoor installation in air-insulated
switchgear. They have a switching capacity capable
of handling the loads occuring at start-up and
shutdown of equipment and plant units both in
normal and in fault state.
Vacuum circuit breakers have particular advantages
for use in systems where the switching frequency in
the operating current range is high, and/or where a
certain number of short circuit breaking operations
have to be reckoned with. Vacuum circuit breakers
of type VM1-T are prepared for auto-reclosing
operations and are notable for their especially high
operational reliability and extremely long service life
with complete freedom from maintenance.
The vacuum circuit breakers of type VM1-T in column
design can be supplied both as individual units for
stationary mounting and mounted on trucks. Their
basic structure is shown in section “Technical data”.
1.2 Standards and specifications
1.2.1 Switchgear manufacture
The switchgear complies with the following
specifications in accordance with DIN VDE and the
relevant IEC publications:
•
VDE 0670, part 1000 and IEC 60694
•
VDE 0671, part 100 and IEC 62271-100
1.2.2 Installation and operation
The relevant specifications are to be taken into
account during installation and operation,
particularly:
•
DIN VDE 0101, Power installations exceeding
AC 1 kV
•
DIN VDE 0100-410, Erection of power installations
up to 1000 V, protective measures
•
VDE 0105, Operation of electrical installations
•
DIN VDE 0141, Earthing systems for special power
installations with rated voltages above 1 kV
•
Accident prevention regulations issued by the
appropriate professional bodies or comparable
organisations. In Germany, these comprise the
following safety regulations:
- Health and Safety at Work Standards BGV A1 and
BGV A3
- Safety guidelines for auxiliary and operating
materials
- Order related details provided by ABB.
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1. Summary
1.3 Operating conditions
1.3.1 Normal operating conditions
Design to VDE 0670, part 1000, “Common
specifications for high-voltage switchgear and
controlgear standards” and IEC publication 60694,
with the following limit values:
•
Ambient temperature:
- M 40 °C
- Maximum 24 hour a 35 °C
- Minimum (according to “minus 25 indoor class”)
- 25 °C
•
Humidity:
- the average value of the relative humidity
measured over a period of 24 h, does not exceed
95%
- the average value of the water vapour pressure,
over a period of 24 h, does not exceed 2.2 kPa
- the average value of the relative humidity, over a
period of one month, does not exceed 90%
- the average value of water vapour pressure, over
a period of one month, does not exceed 1,8 kPa
•
Maximum site altitude:
-
≤ 1000 m above sea level.
1.3.2 Special operating conditions
Special operating conditions are to be agreed on by
the manufacturer and user. The manufacturer must
be consulted in advance about each special
operating condition:
•
Site altitude over 1000 m:
- Allow for the reduction in the dielectric strength
of the air.
•
Increased ambient temperature:
- Current carrying capacity is reduced.
- Provide additional ventilation for heat
dissipation.
•
Climate:
- Avoid the risk of corrosion or other damage, e.g.
to the operating mechanisms, in areas:
- with high humidity and/or
- with major rapid temperature fluctuations.
- Implement preventive measures (e.g. electric
heaters) to preclude condensation phenomena.
Summary of Contents for VM1-T
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