Electrical Noise - Xerox DOCUPRINT N17 Service Manual

7.4.25 Electrical Noise

You were directed to this RAP because electrical noise emissions are interfering with the operation of the
printer. Use this RAP to diagnose and eliminate the electrical noise. Sometimes an arcing electrical
voltage can be the source of the problem. In light of this, particular attention should be directed to the
areas of the HVPS and line voltage.
Initial Actions
• Remove all of the installed options in order to isolate this noise problem. Test the base
printer with no options installed. If the noise problem is eliminated, reinstall all of the optional
components, one at a time, and retest.
Determine which optional component is the source of the noise and replace that component.
• When a cover or printer component is removed and replaced/reinstalled for testing purposes,
ensure that the cover or component is positioned securely into place with all of the proper
hardware (screws) before retesting. Some components, such as the HVPS and the
Transport Chute Assembly, are dependent on ground connections when properly positioned
and secured.
1 Ensure that the printer is properly grounded; that is, ensure that the line voltage is correctly
polarized and the proper ground connection is established between the printer and the wall
outlet.
Y: Go to step 2.
N: Inform the customer that the wall outlet must be properly polarized and that the proper
ground connection must be established.
2 There is an electrical device that might be generating noise around the printer.
Y: Move either the device or the printer to a different location.
N: Go to step 3.
3 There is resistive continuity measured across the Ground Diode Assembly (Fuser area) in one
direction and infinite resistance in the opposite direction.
Y: Go to step 4.
N: Replace the Fuser Assembly.
4 Visually check that the anode side of the Ground Diode Assembly is connected to a tab that is
brushing against the metal part of the Heat Roll.
Y: Go to step 5.
N: Replace the Fuser Assembly if the tab cannot be made to contact the metal tube of the
Heat Roll.
5 The Transport Chute Assembly is grounded to the printer chassis through a Transport Chute rear
mounting screw.
Y: Go to step 6.
N: Make sure that the screw securing the rear of the Transport Chute Assembly to the
printer chassis is secured tightly.
Xerox DocuPrint N17 Service Manual
6/98
www.printcopy.info
7-69 Repair Analysis Procedures (RAPs)