WESTEK Electronics has released the Schaffner model NSG 438 electrostatic discharge gun. It is suited to immunity testing to European Norms and AS/NZS standards.
It can be battery and mains-operated, making it suitable for applications in difficult to reach spots of the equipment under test. The peak discharge voltage of the gun is adjustable from 200V to 30kV in 100V steps. Single or repetitive pulses are provided. For repetitive pulses, frequency is adjustable from 0.5Hz to 25Hz in five steps. This permits a flexible testing regime beyond the scope of normal requirements. This allows users to check the performance of surge suppression components and other critical devices.
The NSG 438 comes with a pulse delivery network that meets the pulse specifications of EN61000-4-2. Other networks providing pulses to ISO10605, ANSI and various MIL standards are available. Test pulses can have positive or negative polarity or alternating polarity. The gun can be triggered with its trigger button or remotely with a control signal. A pulse counter allows forward or backward counting presets to 9999 counts. The NSG 438 is microprocessor-controlled, allowing it to store and recall IEC, ISO and eight user-defined test protocols.
It has a touch-sensitive display with a virtual thumbwheel for parameter setting. Preprogrammed parameters for IEC 61000-4-2/ISO 10605 ensure that the instrument is correctly set up and that the appropriate discharge network has been installed. Test probes and discharge networks can be changed with a twist and pushed into place. The components are coded and generate an error message when not appropriate for a particular testing routine. These settings can also be automatically downloaded from a PC. The NSG 438's memory permits the storage of custom test protocols ready for immediate call-up.
Long test runs can be accommodated with its counter and pre-counter displays. The displays are automatically updated by the occurrence of discharge events. The detector threshold can be adjusted to only include those appropriate to the application.