Electrical; 5.11.1 Major Functions - Brother HL-4000CN Service Manual

5.11

Electrical

5.11.1 Major functions

Fan
Discharges heat out of the printer to prevent too high temperature in the printer.
Harness ASSY AC SW
Composed of the main switch and inlet and controls supply of AC power from the power
source to LVPS.
LVPS STD
The LVP STD is provided with two types, 100/200V and 230V.
Supplies AC power from the power source to the fuser ASSY heater and generates and
supplies stable low voltage DC power used for the logic circuit, etc.
LVPS contains control circuit for the heater of the fuser ASSY, in addition to the power
circuit.
HNB MCU with CPU
Controls printing operation based on the communication with the print controller and
information from the sensor/switch. Incorporates functions of HVPS.
Major functions are as follows:
Supplies high voltage to parts in the print head cartridge ASSY to perform charging,
development, primary transfer and secondary transfer of the print process to the following
parts in the ASSY.
PWBA HNB DRV
Controls parts of motor and so on by the signal from the HNB MCU with CUP and sends
information from the sensors and switches to HNB MCU with CUP. The power from the
LVPS STD is supplied to the HNB MCU with CPU through this PWB. Also, the interlock
switch is mounted on this PWB.
Major functions are as follows:
Controller board
Receives data from high-order unit (host), prints and controls the whole printer.
Communication with the printer controller.
Receive of information from the sensors or switches.
Control of Scanner ASSY
HTC
Refresher
Developer
IDT 1
Recive of information from the sensors or switches.
Control of toner motor in main drive ASSY, DEVE drive ASSY, fuser drive
ASSY, motor ASSY DUP, and holder TDRU ASSY.
Distributing low voltage DC power outputted from LVPS to each component.
Cutting off the 24VDC circuit by the interlock switch
III-40
IDT 2
IDT 1 Cleaner
IDT 2 Cleaner