Emerson 386 Installation, Remove the Shipping Skid large N-ATSs, Supporting Foundation, Mounting

SECTION 1 INSTALLATION

ASCO 386 Non–Automatic Transfer Switches (N–ATSs) are factory wired and tested. Field installation simply requires mounting and connection of service cables, and auxiliary control circuits (if required).

Remove the Shipping Skid (large N–ATSs)

For large N–ATSs, open the front door and remove the four lag screws (2 in front, 2 in rear) securing enclosure to the wood skid.

Supporting Foundation

The supporting foundation for the enclosure must be level and straight. Refer to the applicable enclosure outline drawing included with the switch for all mounting details including door opening space.

If bottom cable entry is used, the foundation must be prepared so that the conduit stubs are located correctly. Refer to the enclosure outline drawing for specified area and location. Provide cable bending space and clearance to live metal parts. When a concrete floor is poured, use interlocking conduit spacer caps or a wood or metal template to maintain proper conduit alignment.

Mounting

Refer to the Outline and Mounting Diagram provided with the N–ATS; it shows all mounting details and instructions.

NOTICE

Protect the non–automatic transfer switch from construction grit and metal chips to prevent malfunction or shortened life of the N–ATS.

Mount the ASCO 386 vertically to a rigid supporting structure. Level all mounting points by using flat washers behind the holes to avoid distortion of the switch.

Auxiliary Cable Boxes for 1000 and 1200 A

For G–design 1000 and 1200 ampere sizes, auxiliary cable boxes are required for all (normal, emergency, & load) bottom or top entry. Be sure to install auxiliary cable boxes if both service and load cables are entering through the top or bottom of enclosure. Consult ASCO Power Technologies.

Be sure that the insulator piece is behind the 260 and 400 ampere transfer switches.

insulator backing piece

Figure 1-1. Insulator for E–design 260 and 400 ampere

Controller Ground

The controller is mounted on the cabinet door. The transfer switch is connected to the left side of the controller by a plug–in harness (two plugs). An add-on DIN rail is provided for some optional accessories and is mounted below the controller on the door.

A grounding wire must be connected to the controller’s lower left mounting stud. Because the controller is mounted on the enclosure door, a conductive strap must be used between the enclosure and the door. This connection provides proper grounding which does not rely upon the door hinges.

Auxiliary Circuits

Connect auxiliary circuit wires to appropriate terminals on transfer switch terminal block TB as shown on the wiring diagram provided with this Non–Automatic Transfer Switch.

Read all instructions on the Wiring Diagram and labels affixed to the non–automatic transfer switch. Note the control features that are provided and review their operation before proceeding.

Insulator Backing Piece for 260 and 400 A

E–design transfer switches rated 260 and 400 ampere are mounted on an insulator backing piece (installed behind the transfer switch). If the transfer switch is removed from the cabinet and then reinstalled, this insulator piece must be placed behind the transfer switch. See Figure 1-1.

1---1