IBM 390E manual Handling Electrostatic Discharge-Sensitive Devices, Grounding Requirements

Handling Electrostatic

Discharge-Sensitive Devices

Any computer part containing transistors or integrated cir- cuits (ICs) should be considered sensitive to electrostatic discharge (ESD). ESD damage can occur when there is a difference in charge between objects. Protect against ESD

damage by equalizing the charge so that	the	machine, the
part, the work mat, and the person handling	the	part are all
at the same charge.

Notes

1.Use product-specific ESD procedures when they exceed the requirements noted here.

2.Make sure that the ESD protective devices you

use have been certified (ISO 9000) as fully effec- tive.

When handling ESD-sensitive parts:

ŸKeep the parts in protective packages until they are

inserted into	the	product.
Ÿ Avoid contact	with	other people.

ŸWear a grounded wrist strap against your skin to

eliminate static on your body.

ŸPrevent the part from touching your clothing. Most

clothing		is		insulative		and retains a charge even when
you	are		wearing		a	wrist	strap.
Ÿ Use	the		black		side	of	a grounded work mat to provide
a static-free work surface. The mat is especially
useful		when		handling		ESD-sensitive devices.

ŸSelect a grounding system, such as those listed

below, to provide protection that meets the specific service requirement.

	Note
The	use of a grounding system is	desirable but
not	required to protect against ESD	damage.

–Attach the ESD ground clip to any frame ground,

ground braid, or green-wire ground.

–Use an ESD common ground or reference point when working on a double-insulated or battery- operated system. You can use coax or

connector-outside shells on these systems.

–Use the round ground-prong of the AC plug on AC-operated computers.

Grounding Requirements

Electrical grounding of the computer is required for oper- ator safety and correct system function. Proper grounding

of the electrical outlet can be verified by a certified electrician.

Introduction15