The QPAC modular controller from Watlow is a modular silicon controlled rectiﬁer (SCR) power controller with plug-in features for ﬂexibility. Bases are rated from 150 to 1000 amperes in one-phase and three-phase, two leg configurations.
A variety of transformers from 120 to 480VAC, along with 50/60Hz operation, enable the QPAC modular controller to operate in applications anywhere. Plug-in control cards set the QPAC's SCR ﬁring modes: solid state contactor, burst ﬁring (zero cross) or phase-angle models and are available with a wide variety of options. High speed fuses are included to protect the SCR modular controller from short circuit currents. 200KA short circuit current rating (SCCR) prevents arc ﬂash.