![background image](http://html.mh-extra.com/html/tektronix/phaser-840/phaser-840_service-manual_1078591071.webp)
60
Phaser 840 and 850 Color Printers
Verifying power supply operation
The power supply is divided into two sections: the AC section used for heaters
and the DC section for control logic, printhead drivers and motors. Verifying the
power supply involves three steps:
■
Checking for proper AC voltage.
■
Inspecting the power supply fuses.
■
Testing for a shorted motor or solenoid driver, which shuts down the
power supply.
Measuring power supply voltages
Warning
AC line voltages are present on the power supply and possibly in the
printer, via the heaters, while the printer is plugged into an AC outlet,
even if the power switch is off.
1.
Turn off the printer and unplug it from its power outlet.
2.
AC Input:
With a DMM set to measure AC voltages, measure the
power being supplied to the printer; it should measure between 87 to
128 VAC (115 VAC nominal) or 174 to 250 VAC (220 VAC nominal).
3.
Proceed to the step, “Inspecting the power supply fuses” below.
If a heater shorts, F2 or F3 opens. The power supply does NOT shut
down, however, a
Service Required
error code is displayed on the
front panel.
Required tools
■
TORX T-20
screwdriver
■
Digital multi-meter (DMM)
Summary of Contents for Phaser 840
Page 11: ...xii Phaser 840 and 850 Color Printers ...
Page 65: ...54 Phaser 840 and 850 Color Printers ...
Page 101: ...90 Phaser 840 and 850 Color Printers ...
Page 125: ...114 Phaser 840 and 850 Color Printers ...
Page 134: ...Service Guide 123 Clearing PostScript NVRAM menu item ...
Page 135: ...124 Phaser 840 and 850 Color Printers ...
Page 166: ...Service Guide 155 Figure 1 Cabinet FRUs 7 5 6 8 1 2 4 0388 21 3 9 9 ...
Page 170: ...Service Guide 159 Figure 3 Paper path FRUs 0388 80 2 1 5 11 10 9 12 6 4 3 7 13 8 11a 11b ...
Page 172: ...Service Guide 161 Figure 4 Motor and fan FRUs 0388 14 7 4 3 5 6 2 1 ...
Page 174: ...Service Guide 163 Figure 5 Circuit board FRUs 4 3 5 2 1 9 7 6 8 10 11 13 0388 81 12 7a ...
Page 176: ...Service Guide 165 Figure 6 Solenoid and clutch FRUs 4 5 3 2 1 0388 23 ...
Page 182: ...Service Guide 171 Figure 9 High capacity PaperTray 0388 65a 1 2 ...