Argantix KDC 100-100, User Manual

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User Manual
KDC Series II DC Power Supplies 71
An over voltage-under voltage comparator monitors the rectified input AC voltage and sends
isolated logic signals to the controller if the mains voltage is not within the operating range.
Each of the DC output modules is synchronized to a common frequency, 93.75 kHz. The
reference clock is generated from a crystal-controlled oscillator on the power supply board. The
oscillator frequency is divided down to provide three separate 93.75 kHz references; each
separated by 120 degrees of phase from the other two.
The three phase AC mains is always active on the DC output modules and the DC supply board;
there is no master switch or circuit breaker. The chassis is turned on or off by a small switch on
the front panel. This switch applies or removes power from the DC supply board PWM controller
chip. When the power to the PWM chip is removed, the fly-back converter stops switching, all the
bias supplies discharge to zero, and the complete unit is put in an “off” state.