EEC SE 7430, Руководство пользователя

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4.3.3 Hardware
The Hardware menu contains important system parameters which must be set prior to performing
tests. Touch the Hardware icon and the following screen will appear:
The touchscreen can be scrolled downward to see the remaining Hardware parameters. Upon
scrolling down the remaining items appear as follows:
4.3.3.1 Smart GFI
The high voltage power supply of the SE is internally referenced to earth ground. Since the leakage
current measuring circuit of the instrument monitors only current that flows through the return
lead the possibility exists for current to flow directly from the high voltage output to earth ground
without being measured. The SmartGFI (Ground Fault Interrupt) circuit monitors the current
between the high voltage output and earth ground. Therefore, if the operator touches the high
voltage lead and earth ground, the instrument will detect this hazardous condition and shut off
immediately.
SmartGFI goes beyond a standard GFI circuit by automatically determining the return
configuration of the DUT (grounded or floating) and enabling or disabling depending on the
situation. When the SE’s Return lead is floating, the SmartGFI circuit enables, protecting the test
operator from electric shock. When the SE’s Return lead is earth grounded, the SmartGFI circuit
disables and the instrument operates in a grounded return mode of operation. If the GFI were to
remain active in this state, the tester would continuously fail since all current is returning through
earth ground. By disabling the SmartGFI circuit and operating in a grounded return mode, SE
allows the user to perform tests on devices that have their chassis’s earth grounded by the test
fixture or test environment.