Features Of FCMA Soft Starter

What is FCMA Soft Starter?

  • The harmonic free, rugged magnetic soft starter for motor starting.
  • FCMA is an acronym for flux compensated magnetic amplifier which is basically a modulated inductive impedance.
  • When connected in series with the motor the FCMA reduces the starting current to a low value.
  • The impedance of FCMA decreases with increasing motor speed by flux compensation thus incrementing the motor voltage without sleep to keep the current constant till motor reaches 90% speed (pullout torque).
  • The motor current now drops to its normal value depending upon the load demand.
  • The motor voltage increment is typically from 50% at start to 95% at full speed gradually.
  • Ideally suited for centrifugal loads. The FCMA is further bypassed by a suitable contactor so that the motor runs at line voltage.
  • The starting current and voltages are purely sinusoidal without harmonics as the flux compensation technology operates the FCMA core always in the linear unsaturated zone. The starting current value is the minimum theoretical value as governed by the motor torque margin and load torque demand.
  • Accelerating torque is always maintained larger than 10% throughout the speed range to avoid critical speed resonance.

Features Of FCMA Soft Starter

  • Suitable for extreme weather conditions-EPOXY caste unit
  • No electronic components
  • Starting current limit up to 1.P.U
  • Starting of Motor with limited KVA
  • In built Bypass system for full voltage during running
  • No Internal-External cooling required
  • Harmonic free
  • Less maintenance
  • Run Indoor and outdoor models in Line or in Phase models available
  • Sinusoidal Wave form Built in bypass for full voltage
  • Amplitude control
  • Unique FCMA technology

FCMA Technology

  • Flux compensation is basically a system where two sinusoid fluxes are imposed on a core leading to a net sinusoidal flux which controls the impedance of the winding.
  • The FCMA fundamentally consists of a main and compensating winding wound on a single magnetic core. The main winding is excite by the motor current and the compensating winding by the counter emf generated by the motor.
  • The net flux in the core is the vector sum of the two fluxes. If the windings are connected in phase opposition then the net flux is the scalar subtraction of the two fluxes.
  • With the decrease in net flux the impedance of the main winding decreases as the motor speed increases. This allows the motor voltage to increase gradually and steplessly form say 50% to 95% with the motor speed.

FCMA Application For Soft Starting Of Motors

Sequence –

Line contactor closes & Motor starts at low current, FCMA controls starting current and accelerates motor to full speed . Motor voltage increases from 50% to 95% keeping current constant. Run contactor closes after time T or Speed S Motor. runs in normal load condition.