Epson TM-FX2180 manual Power Supply Circuit Operation, Board Input Voltage Fuse F1 Rating

EPSON FX-2180 Service Manual

2.1.2 Power Supply Circuit

The printer can be powered by one of the following three power supply boards: C166 PSB (120 V), C166 PSE (220 – 240 V), or C244 PSH

(120 V / 220 – 240 V). The boards function in the same way, except each board has a different primary circuit. The table below lists the input voltages and fuse ratings of the boards.

Table 2-1. Power Supply Board

Board	Input Voltage	Fuse	F1 Rating
C166 PSB	103.5 – 132 V	3.15	A / 125 V
C166 PSE	198 – 264 V	T 2.0 AH / 250 V
C244 PSH	85 – 138 V / 187 – 276 V		5HT4

2.1.2.1Power Supply Circuit Operation

The power supply board has two DC power outputs: one for the control circuit and one for the printer mechanism. The table below lists the applications of the output voltages.

Table 2-2. Power Supply Output Applications

Output Voltage		Applications
+5 VDC	∙	Control circuit board logic
	∙	Sensors
	∙	Control panel LEDs
+35 VDC	∙	CR motor
	∙	PF motor
	∙	Print head

Chapter 2 Operating Principles

When AC power enters the printer from an external power source, the filter circuit removes the noise. Then the AC voltage undergoes full-wave rectification and is smoothed to produce direct voltage. In the C244 PSH board, the AC voltages undergo voltage doubler rectification in the automatic switching IC and are smoothed to produce direct voltage. The voltage is fed to the gate port for switching FET Q1 through resistors R18 and R31. Then the switching circuit operates.

The secondary smoothing circuit produces a stepped down +35 VDC voltage. The +5 VDC voltage is generated and stabilized by feeding the +35 VDC voltage through the +5 VDC power supply circuit. The power supply circuit includes a ZC-RCC (zero cross-ringing choke converter), which contributes to the power supply circuit’s high stability, efficiency, and portability.

The secondary circuit system of the power supply circuit includes the Operate (power) button. The Operate button is located on the printer’s control panel and controls the power supply circuit.

A+35 V line constant voltage control circuit and over-current/over-voltage protection circuits are provided to protect the printer and control circuits.

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