Auto-Starter Transformers for Korndoffer Systems

TMC manufacture a comprehensive range of three phase open star auto transformers for reduced current motor starting. These transformers can be built to BS 587 & BS 4941in conjunction with BS EN.60947-4.

CONSTRUCTION:-

These transformers are naturally air cooled and are manufactured with Class ‘F’ materials ( 155 ˚C ) The windings are vacuum varnish impregnated to DEF31A Specification, and if required the transformer can be further enveloped in a tropical varnish for marine environments.

A top mounted terminal panel is provided normally with brass screws or copper busbars for termination.

Transformer sizes & weights are dependant on the information supplied below. If there are size restrictions we may be able to accommodate them in the design. Enclosures suitable for floor mounting can be supplied with detachable plates for entries. Please state your IP rating.

HP/kW RANGE:-

3/500HP or 2/400kW larger sizes can be manufactured on request, contact the TMC design team for a quotation.

INPUT/OUTPUT VOLTAGES:-

Standard primary input range, 208, 400, 690, & 3.3kV 3 phase 50/60Hz. Alternative input voltages can be catered for on request. Standard output tapping range, 50%, 65% 80% of nominal primary input voltage. TMC can supply various percentage output taps to suit your motor maximum starting or supply current. Ask us for assistance.

DUTY RATINGS:-

Standard motor starts per hour (Single phase) are as follows:- 2, 15, & 40 (Re: BS 587) 3, 12, & 30 (Re: BS 4941)

Other popular duty ratings SPH:- 4, 6, 8, & 20.

Note, other duty ratings can be catered for.

CIRCUIT PROTECTION:-

Due to their nature, auto-starter transformers can be abused by exceeding their designed duty rating ( SPH. ) It is highly recommended that N/C thermal cut-outs are provided. These are imbedded the windings and then wired to terminal blocks on the panel provided. The thermal cut-outs should be wired in series with main input contactor coil.

 
 

PLEASE CONTACT TMC SALES FOR A FREE ESTIMATE OR FURTHER ASSISTANCE WITH DESIGNING THE EXACT UNIT FOR YOUR APPLICATION.