SATURABLE REACTORS Saturable reactors utilize the large change between unsaturated and saturated permeabilities of their cores to delay current for a preset period of time. Similarly, once saturated in the forward direction, they act as a diode temporarily blocking current in the reverse direction. (Figure 1) MAGNETIC SWITCH PROTECTION (MSP) MSP devices made with Metglas®cores have dramatically enhanced the reliability and overall lifetime of pulse power systems. By using a saturable reactor in series with either a semiconductor or thyratron switch, the circuit designer can reduce losses in the switch and extend its life. The saturable reactor is designed to hold-off current until the switch becomes fully conductive (Figure 2). This delay reduces the overlap between current and voltage in the switch, thereby reducing power absorber in the switch. MSP also offers other advantages. Higher didt's to the load are safely achieved by waiting for full conductivity in semiconductor switches. The diode-like characteristic of a saturated reactor provides time for switch recovery