Voltage Measurements - Xerox Phaser 6250 Service Manual

6.
Before measuring voltages make sure the printer is switched ON, the Imaging
Unit and the paper trays are in place, and the interlock switches are actuated,
unless a troubleshooting procedure instructs otherwise.
7.
All voltage values given in the troubleshooting procedures are approximate
values. The main purpose of voltage readings is to determine whether or not a
component is receiving the correct voltage value from the power supply and if
gating (a voltage drop) occurs during component actuation. Gating signals may
be nothing more than a pulse, resulting in a momentary drop in voltage that may
be difficult or impossible to read on the average multi-meter.
8.
When a troubleshooting procedure instructs you to replace a non-spared
component and that component is part of a parent assembly, you should replace
the entire parent assembly.
9.
Ensure that you are using a supported media size and type, refer to "Media and
Tray Specifications" on page 1-14.

Voltage Measurements

1.
Power and signal grounds are connected to the frame ground. All circuit
troubleshooting can be performed using the metal frame (chassis) as the
grounding point. To locate connectors or test points, refer to the section "Plug/
Jack Locator Maps" on page 10-2 or "Wiring Diagrams" on page page 10-12 for
more information.
Unless otherwise specified, the following voltage tolerances are used within this
section:
Stated
+3.3 VDC
+5.0 VDC
+24.0 VDC
0.0 VDC
Error Messages and Codes
Measured
+3.135 to +3.465 VDC
+4.75 to +5.25 VDC
+21.6 to +26.4 VDC
Less than +0.5 VDC
3-5