Canon FAX-L350, Service Manual

Page: 44 / 213

1-31
FAX-L350 Chapter 1: General Description
5.3 Servicing Cautions
5.3.1 Damage from static charge
This unit contains contact sensor and printed circuit boards equipped with ROM, RAM, custom chips, etc.
These electronic components are susceptible to damage caused by static charge.
When disassembling this unit, take care to prevent static charge.
Static electricity
Electrostatic discharge damages electronic components and alters their electrical
characteristics. Even plastic tools and hands without grounding wrist straps will generate
enough static electricity to damage electronic components.
The following equipment is needed to prevent electrostatic discharge damage:
• A earthed conductive mat
• Grounding wrist straps
• A cord with alligator clips to ground this unit’s metal chassis
If you do not have any of the above on hand (during on-site servicing), follow the alternate measures below:
• Use a grounding bag to store and transport printed circuit boards and electronic devices.
• Avoid wearing silk or polyester clothing and leather-soled shoes. Wear cotton clothing and rubber-soled
shoes instead.
• Avoid servicing this unit in a carpeted room.
• Before servicing this unit, touch this unit’s grounded terminals to discharge any static charge.
• Wear grounding wrist straps and ground this unit’s metal chassis.
• Always handle the circuit boards and devices along their edges. Do not touch the components and termi-
nals with your fingers.
Electric shock when carrying out work with the fax turned on
When you must service the fax with the power cord plugged in, you must not ground your
body with grounding wrist straps. This is to prevent electricity passing to your body and
causing electric shock.
5.3.2 Scanner section
a) Contact sensor
• Handle contact sensors with care to prevent scratching or smudging of the scanning surface. Scratches
or smudges can cause vertical stripes, etc., to appear on the scanned image.
b) ADF rollers
• Be careful not to scratch the ADF rollers. If the rollers are scratched, paper jams may result.
c) Lubrication points
• Document feed roller.