B2342
Emax VF
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Doc. No
Model
Apparatus
Scale
Page No
1SDH000909R0001
type B: between 3 circuit-breakers (2 power su emergency)
type C: between 3 circuit-breakers (2 power su bus-tie)
type D: between 3 circuit-breakers (3 power supplies / a single closed circuit-breaker)
The emergency power supply is generally supplied in order to substitute the normal power supply in two cases:
- to supply safety services for people.
- to supply essential parts of the installation for other than the safety services.
The change over from the normal supply to the emergency supply, can be done manually (with a local or remote control) or automati-
cally. For the change over, the circuit-breakers must be supplied with the necessary accessories for the electrical remote control and
for electrical and mechanical interlocks provided for the changing over.
The accessories can be for example:
- the shunt opening release
- the shunt closing release
- the motor operator
- the auxiliary contacts
For the change over, the customer can use a suitable electronic relay, whose diagram is supplied by ABB SACE. The mechanical
interlocks between two or three circuit-breakers are made by means of cables that can be used for circuit-breakers installed, either
side-by-side or one over the other.
Table of feasible mechanical interlocks between two or three circuit-breakers
Type of
interlock
Number
of circuit-
breakers
Type of circuit-breaker
Possible interlocks
A
TWO
A normal power supply unit and an emergency
unit.
The first circuit-breaker can be closed only if the
second (emergency) breaker is open.
B
THREE
Two normal power supply units and an emergency
unit.
The first and third circuit-breakers can be closed
only if the second (emergency) breaker is open.
The latter can be closed only if the first and third
are open.
C
THREE
A unit of 2 supplies and a bus-tie.
The two half-busbars can be supplied by a single
transformer (bus-tie closed) or simultaneously by
both (bus-tie open).
One or two circuit-breakers out of three can be
closed at the same time.
D
THREE
A unit of 3 supplies / a single closed circuit-break-
er. Three supplies (generators or transformers) on
the same busbar for which parallel operation is
not allowed.
Only one of the three circuit-breakers can be
closed.
10.3. Notes for Emax LTT Low Temperature accessories
The SACE Emax VF LTT, switch disconnector designed for low temperature environment, is accessoriable only with the standard
opening, closing and undervltage releases at 220V AC/DC.
The geared motor for the automatic charging of the spring is available with a special version for low temperature at 220V AC/DC.
Auxiliary contacs, terminals and fixed parts are in common to the Emax VF product.
Transparent pushbuttons protection covers, IP54 door protection, interlocks, homoploar toroid, time delay device for undervoltage
release and external neutral current sensors are not available.
10.4. Spare parts and retrofitting
Spare parts
The spare parts available are:
- Arcing chamber
- Stored energy operating mechanism (*) (Type “A”)
- Closing springs kit (*) (Type “A”)
- Contact kits for clamp disconnection for a fixed part of the removable circuit breaker
- Creeping earth contacts (for withdrawable version)
- Frontal shield kit complete with caps and side shields
- Safety shutters fixed part shutters
- Transparent protection for PR122/VF release
- Opening solenoid for maximum current release PR122/VF
- Testing front connecting cap for relay
- SACE PR030/B power supply unit
- Lubricating grease for stored energy operating mechanism
- Terminal board for fixed
- Creeping contacts, fixed part
- Creeping contacts, movable part
- Dust tab for door of cell
- Extraction crank
- Lifting plates pair
- Front escutcheon plate for Ronis-type key lock
For further details, ask for the ABB SACE spare parts catalogue.
(*) Subject to the customer’s approval, ABB can replace “A” type parts.
