
Servicing
Safety Precautions
Thermo Fisher Scientific
Model 49
i
Primary Standard Instruction Manual
6-3
Safety Precautions
Read the safety precautions before beginning any procedures in this chapter.
WARNING
The service procedures in this manual are restricted to qualified
service representatives.
If the equipment is operated in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired.
The Model 49
i
Primary Standard is supplied with a three-wire grounding
cord. Under no circumstances should this grounding system be defeated.
Equipment Damage
Some internal components can be damaged by small
amounts of static electricity. A properly grounded antistatic wrist strap must
be worn while handling any internal component (
). If an
antistatic wrist strap is not available, be sure to touch a grounded metal
object before touching any internal components. When the instrument is
unplugged, the chassis is not at earth ground.
Handle all printed circuit boards by the edges.
Do not remove the LCD panel or frame from the LCD module.
The LCD polarizing plate is very fragile, handle it carefully.
Do not wipe the LCD polarizing plate with a dry cloth, it may easily scratch
the plate.
Do not use alcohol, acetone, MEK or other Ketone based or aromatic
solvents to clean the LCD module, use a soft cloth moistened with a
naphtha cleaning solvent.
Do not place the LCD module near organic solvents or corrosive gases.
Do not shake or jolt the LCD module.