Table 1-4 Low voltage power supply DC power specifications (continued) DC voltage Behavior +5V +5V Off during Sleep mode (sleep level1, active off and inactive off) +3.3V +3.3VA Constantly supplied +3.3VB Off during Sleep mode (inactive off) +3.3VC Off during Sleep mode (active off and inactive off) +3.3VD Off during Sleep mode (sleep level1, active off and inactive off) Over-current/over-voltage/overload protection The over-current/overvoltage protection automatically stops the DC voltage to the product components whenever an excessive current or abnormal voltage is detected.
The overload protection automatically stops the DC voltage to the product components whenever the temperature of the low-voltage power supply PCA rises to specified degrees. The low-voltage power supply has a protective circuit against over-current, over-voltage and overload to prevent failures in the power supply circuit. If DC voltage is not being supplied from the low-voltage power supply, the protective function might be running. In this case, turn the power off and unplug the power cord. Do not turn the product switch on until the root cause is found and corrected.
The DC controller determines a low-voltage power supply failure and notifies the formatter when the protective function runs. In addition, the low-voltage power supply has three fuses to protect against over-current. If over-current flows into the AC line, the fuse blows to stop AC power. Safety interruption For user and service technician's safety, the product interrupts the power supply of +24V by turning off the interlock switch. The DC power to the following components is interrupted: ● High-voltage power supply ● Fuser motor The remote switch control circuit turns on or off the product so that the AC power flows even the power switch is turned off.
Be sure to unplug the power cord before disassembling the product. Power supply voltage detection The power supply voltage detection controls the fuser properly according to the voltage. The DC controller detects whether the low-voltage power supply voltage is 100V or 220V according to the POWER SUPPLY VOLTAGE signal (/PSTYP100). ENWW Engine control system 11