PAK SERIES – Reinforced Substation for Tunnelling

PAK series, medium voltage electrical mobile substation for tunnelling and mining installation, is a reinforced unit, that can be installed on a truck, skid mounted or placed on a wagon, for easy handling in the tunnel.

Extremely robust and resistant to heavy mechanical stress, PAK substation can operate in extreme environmental conditions.

It conforms to European Standard IEC, Tunnelling and Mining Rules.

Construction

PAK substation is manufactured with 5 and 3 mm thick cold-worked and continuous welded steel plate.

Substation doors are mounted by inox steel hinges. Bolt, screws and mechanical devices have anti-corrosion treatment.
Enclosure, with closed door, is IP549.

Painting

Substation is painted and finished to the following specification:

• sheet degreasing with synthetic thinner
• sanding with scotch-brite 3M for zinc passivated steel supports
• one coat antirust epoxide primer, 25 micron thick
• two coats epoxide enamel, 60 micron thick

Medium Voltage Switchboard

The medium voltage switchboard is installed in a separate section segregated from the LV side, which includes:

• an earthing switch disconnector on the incoming line
• an on load switch disconnector with tripping coil combined with current limiting fuse (switch fuse combination)
• an earthing switch disconnector on the outgoing line

Transformer

To comply with current standards, different types of transformer can be provided with the substation according to customer requirements:

• Cast resin transformer (50-1250 KVA)
• Silicon oil transformer (50-1250 KVA)
• Dry-type transformer (50-1250 KVA)

Low Voltage Switchboard

The low voltage switchboard is fitted into a separate section segregated from the MV side. It includes the main circuit breaker to protect the transformer against short circuit, overload and earth-fault.

The design arrangement of the LV utilities is manufactured to suit customer specifications and can include moulded case circuit breaker (MCCB), load break disconnector combined with current limit fuses, earth leakage protection, starters, small PLC and measuring devices as well as automatic power factor correction unit.