The TC3000 SCR assembly is a general purpose three phase power controller for all constant resistance or inductive loads up to 500A/500Vac. The TC3000 fires evenly on all phases to match the load to the generator supply. Three wire wye or delta, four wire wye with neutral and six-wire inside delta load configurations can be controlled. Resistive load firing modes include logic firing for action as a solid state contactor, single cycle for special applications, fast cycle for quick acting heaters and slow cycle for large loads. Phase angle firing is available for inductive loads. Inputs are logic or analog. The TC3000 is phase rotation insensitive. The unit is shrouded in a protective cover with commissioning and diagnostic points available on the front. Protective measures include built-in high speed fuses with optional fuse-fail microswitches, snubbers and varistors and SCR quenching action on any of several operational alarm conditions. Cooling at 100A and up is by fans, with over