The KBWS PWM (pulse width modulated) controls are designed to operate PWM and SCR rated Permanent Magnet motors ranging from 1/50 HP to 11⁄2 HP. They operate at a switching frequency greater than 16 kHz to provide high motor efficiency and quiet operation. Another advantage of PWM is higher output voltage (up to 130 Volts DC for 115 Volt AC line and 220 Volts DC for 208/230 Volt AC line) which provides increased motor speed.
The KBWS contains pulse-by-pulse current sensing, which provides short circuit protection and prevents control damage due to commutator arcing. Permanent magnet motor demagnetization is completely eliminated because current peaks are reduced to safe levels. The controls contain an AC line inrush current limiter (ICL) which reduces the AC line surge current during startup.