Protective functions The low-voltage power supply circuit utilizes overcurrent and overvoltage protective functions. The protective functions automatically interrupt output voltage to prevent power supply failures. These failures occur from an excessive current flow that is caused by a short circuit on the load side, or from an abnormal voltage increase. When the dc voltage is not output from the low-voltage power supply circuit, the overcurrent or overvoltage protective function might be activated. If it is activated, turn off the printer, correct the problem in the failure loads, wait about two minutes, and then turn on the printer.
The circuit contains a power fuse (F1) which breaks and cuts off the power supply if overcurrent flows through the ac line. Figure 46. Printer power supply C8523-90921 Basic system configuration 79