VM1 - INSTRUCTION MANUAL BA 504/05 E
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1. Summary
1.1
The vacuum circuit breakers of type VM1 are
intended for indoor installation in air-insulated
switchgear.
Within the limits of their technical data, they have
a switching capacity which is sufficient to
withstand the loads occurring during the
switching on and off of equipment and switchgear
components under normal and fault conditions.
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 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 in column
design can be supplied both on withdrawable
parts and as individual
units for stationary mounting and mounted on
trucks. Their basic structure is shown in section
"Technical data".
1.2
1.2.1
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
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.
General
Standards and specifications
Switchgear manufacture
Installation and operation
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:
- Maximum
- Maximum 24 hour average
- Minimum (according to "minus 25
indoor class")
• Humidity:
- the average value of the relative
humidity, measured over a period
of 24 h, does not exceed
- the average value of the water
vapour pressure, over a period
of 24 h, does not exceed
- the average value of the relative
humidity, over a period of one
month, does not exceed
- the average value of the water
vapour pressure, over a period
of one month, does not exceed
• 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.
+ 40 °C
+ 35 °C
- 25 °C
95%
2.2 kPa
90%
1.8 kPa