|
The Building Blocks |
||
|
|
||
|
|
|
The Building Blocks |
||
|
|
||
|
|
|
Terminals |
|
|
Terminals are contained within metalclad compartments, for incoming and outgoing mains in accordance with IEC 298. An undrilled gland plate is provided suitably positioned to allow dry-type glanding and space for the cable tails to be made off. An earth terminal is provided. |
|
|
|
Copper bars are contained within segregated metalclad ducts, the moulded three-phase supports adequately bracing the conductors and spacing the bars for direct connection to the isolator. Rating 750A or 1500A per tier. |
|
The direct drive isolator is bolted directly to the steel bus-duct completely enclosing all live parts. An inspection window provides means to confirm the 'off/earth' position. This can be visually confirmed in the Compact Range, prior to opening the door. |
|
|
The operating shaft has provision for the application of padlocks, and the door interlock utilises the 'female' part on the isolator shaft, to prevent mal-operation. Auxiliary contacts are driven directly by the operating shaft and the main contact drive employs a mechanism that ensures the main contacts cannot be forced open under fault conditions. The isolator structure forms a metalclad compartment within the starter main enclosure, to IEC 298. |
|
|
Voltage Rating: 7.2kV (for 6.6kV) |
|
|
Current Rating: 400A |
|
|
Prospective Fault Rating: 48kA |
|
|
|
An on-load isolator is also available, together with interlocked earth switch as appropriate. A metalclad window is provided to view the contact gap in the off position. The switch uses tubular contacts with the load-breaking mechanism within the contacts, so preventing flash hazard . |
||||
|
Voltage Rating: |
11kV |
||||
|
Current Rating (A): |
400 |
630 |
1250 |
||
|
Fault Withstand (kA/second): |
20/1 |
25/1 |
25/3 or 31.5/1 |
||
|
The fuse module will accept single, double and triple barrel fuses which means that all currently available motor starter and distribution type fuses can be fitted. Fuse blown indicators can be provided (striker pins). |
|
|
The supply to the fuses is via fully fault-rated copper bars, and (to 6.6kV) the primary fuses for the control circuit transformer are clipped directly to the load side of the main fuses. Mains connections from the fuses are made in flexible EPR/CSP Type 4 cable (BS 6195). |
|
|
|
Fixed or draw-out contactors are available to 6.6kV, and fixed only type to 11kV. |
|
When fixed type contactors are used, earthing of the outgoing terminals (i.e. the motor) can be achieved by the use of an earthing switch or, in the Compact Range, the use of a third 'earth' position on the isolator. |
|
|
Contactor Ratings |
||||
|
Vacuum contactors of the following ratings may be selected: |
||||
|
Voltage (kV) |
3.3 |
6.6 |
11 |
|
|
AC3 Current Ratings (A) |
315 |
400 |
300 |
|
|
400 |
400 |
|||
|
630 |
||||
|
Draw out Contactors |
|
|
Up to 6.6kV, the 400A contactor can be mounted in a draw-out chassis incorporating an earthing feature which automatically earths the outgoing terminals when the contactor is withdrawn, unless inhibited for testing procedures. Safety and security are enhanced by the plugs and sockets being in clear view, when fully isolated, in the withdrawn position. |
|
Options |
|
Other ratings and types (i.e. SF6) may be utilised for particular applications |
