Removing And Installing Circuit Boards
CAUTION
Circuit boards for the Impact FXS system are susceptible to damage caused by electrostatic discharge,
and you must keep this fact in mind as you handle the circuit boards. Refer to the Comdial publication
IMI01-005, Handling Of Electrostatically Sensitive Components, for general information Specific
handling precautions are also included in this installation instruction.
The Impact FXS system may include some installed circuit boards when it arrives at your site. The system
consists of two parts—the computer portion and the telephony portion. In the telephony portion of the Impact
FXS system, the equipment cabinet provides universal slots that will accept either line or station boards.
When removing or installing circuit boards in the Impact FXS cabinet, you must install a static discharge wrist
strap on your bare wrist, and adjust it for a snug fit. Be sure that the strap is touching bare skin and is not isolated
by clothing. Connect the wrist strap cord between the wrist strap and a AC or earth ground.
Unless a circuit board has a pre-charge port on its front panel, disconnect the AC power cord from the AC service
outlet and disconnect the cable between the cabinet and any external battery back-up assembly before you remove
or install the circuit board. However, if the board does include a pre-charge port, you can connect a standard
telephone handset cord between the pre-charge port on the circuit board and the pre-charge port on the power
supply assembly and remove or install the circuit board while the system is operating.
Whenever you remove a circuit board from the cabinet, immediately place the board in a static protection bag
while you still have your wrist strap in place and properly grounded.
Creating a Static Safe Work Area
When removing circuit boards from an installation location for servicing, always transport them to a static-safe
work area in static protection bags. If you do not already have a static-safe work area, you can create one by
arranging a work area as detailed in the illustration.
Removing And Installing Circuit Boards 3
Installing The SCbus Interface Board
IMI89–313
Typical Earth
Ground
Static
Wrist
Strap
ESD Protective
Mat
ESD Protective
Mat
ESD Protective
Worksurface
Static 2
Common Point Ground
Creating a Static-Safe Work Area
