Site mains supply

In many instances, due to the low environmental impact, the preferable option is a 415 volt 3-phase (125 amp per phase, with a HRC fuse or Class D, or above, circuit breaker) mains supply.

Static generator

For contracts where mains supply is unavailable and access is restricted for a mobile rig to be used, 250Kva static generators can be provided by SMD as an alternative (refer Fig.11.5.1b).

Dimensions of 3.8L x 1.5W x 2H (metres) and weighing in at approx. 3.7t (without fuel)

Where a static generator is required, it should be positioned in a well ventilated area and consideration should be given by the Structural Engineer to its location to avoid overloading of the steel frame.

Stud welding rectifier

The above are sufficient power supply options for the Nelson Nelweld 6000 series rectifier(s) to be used.

Stud welding rectifier

Specification** Voltage 415 @ 50Hz Socket type 125-6h (5 Pin, 3 Phase + N + E + Pilot) Amperage 125 amps per phase Protection HRC fuse preferred, if using circuit breaker Class D or better

• Typical load during weld cycle 350 to 400 amps per phase on the incoming for 1.5 seconds.
• Inrush current up to 1300 amps for 1 to 2 cycles

Stud welding rectifier

Implementation** Fig.11.5.1c indicates the type of plug and socket that is required to connect stud welding rectifiers to a site mains supply. All rectifiers supplied by SMD will be fitted with this type of plug. Sites must terminate the mains supply at a compatible socket. Should power be supplied by a generator, it must not be supplying power to other plant as it may overload the generator capacity.

Mains outlets need to be available at every other floor level. Studs can be installed to a 60m radius from the outlet location. For floors in excess of 1500m² more than one power point may be required.

SMD do not use these plugs and sockets when using a static generator. When a generator is utilised (min 250kva) for the power supply the rectifier must be hard wired into it (by others).