Agilent Technologies Switch/Measure manual Before they reach the module or the Analog Buses

3Introduction to the Plug-In Modules for the 34980A

Transients

The 34921A, 34922A, 34923A, 34924A, 34925A, 34931A, 34932A, 34933A, 34937A, and 34938A modules are designed to safely withstand occasional transient overvoltages up to 1000 Vpeak. Typically, these transient overvoltages result from switching inductive loads or from nearby lightning strikes. The lightning- caused transient overvoltages that may occasionally occur on mains power outlets may be as high as 2500 Vpeak.

The 34941A, 34942A, 34945A, 34946A, 34947A, 34950A, 34951A, 34952A and 34959A modules are intended for only low- voltage applications, and should not be connected to circuits that may generate or conduct large transient voltages.

WARNING	Do not connect any of the modules directly to a mains power
	outlet. If it is necessary to measure a mains voltage or any circuit
	where a large inductive load may be switched, you must add
	signal conditioning elements to reduce the potential transients
	before they reach the module or the Analog Buses.

High Energy Sources

These modules are designed to handle inputs up to their rated currents or their rated powers, whichever is less. Under certain fault conditions, high energy sources could provide substantially more current or power than a module can handle. It is important to provide external current limiting, such as fuses, if the module inputs are connected to high- energy sources.

CAUTION	Install current limiting devices between high energy sources and
	the module inputs.

94 34980A User’s Guide