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a foot operated switch, which is convenient when testing in a humidity chamber. In the
AUTO mode, the discharge sequence specified in ANSI/ESD STM11.31 along with the
scope settings are controlled automatically by the ETS Energy Calculation Program.
The discharge waveform generated by the Model 4431 meets the requirements of
ANSI/ESD STM5.1 Electrostatic Discharge Testing - Human Body Model. A typical
discharge waveform measured with the discharge electrode in direct contact with the
capacitive sensor is shown in Figure 4.0-2.
Figure 4.0-2: Discharge waveform
A spring-loaded lever clamps the discharge electrode against the bag, capacitive
sensor and spring loaded ground electrode with approximately 5 pounds of force,
ensuring consistent and repeatable results.
Included with the Model 4431EV are the following interconnect cables and accessories
shown in Figure 4.0-3a:
Figure 4.0-3a: Model 4431-EV cables and accessories
1. BNC-BNC (2) cables for connecting voltage output signals to oscilloscope
2. BNC cable from CT-1 to oscilloscope (Model 4431-EV only)
3. 50 Ohm terminator
4. USB cable from computer to the oscilloscope (Model 4431-EV only)
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