Instek GPT-9802-NIST Performance Hi-Pot Tester, AC 200VA AC/DC Withstanding Voltage Tester, with NIST

The GPT-9800 Series Electrical Safety Tester, with high durability and multiple user-protection design, look to meet the test requirements of a variety of safety standards, such as IEC, EN, UL, CSA, GB, JIS, and other safety-related tests for the electronic products and components. The GPT-9802 is capable of performing both AC and DC withstanding tests. The series of safety tester is built upon a high-efficiency PWM amplifier platform with AC 200VA maximum output capacity to impede the influence from the voltage fluctuation of the input AC source. This ensures a stable voltage supply for all the tests of the GPT-9800 Series.

Targeting user's protections, the GPT-9800 Series uses a combination of hardware and software controls to improve safety: A self-check is performed to make sure all the functions and operations are under normal condition each time when the tester is turned on; the Zero Crossing Turn-On design imposes the output voltage to always begin at the zero crossing of a sine wave to avoid the impact of surge voltage output; and the output voltage is automatically cut off (within 150µs) when abnormal output voltages have been detected or when the upper or lower current limits have been reached during testing. To protect operator from hazardous injury, the GPT-9800 Series automatically discharges the DUT after test (within 200ms) each time to eliminate excessive voltage that remains on the DUT. To further ensure safety, the interlock key can also be used as double protections to prevent inadvertent operation.
 
The GPT-9800 Series, equipped with a simple & clear panel layout, a high resolution dot matrix LCD display, and color LED indicators, allows operators to interpret measurement results easily and quickly. All major test functions, including AC withstanding (AC 5kV/40mA), DC withstanding (DC 6kV/10mA), insulation resistance (DC 50V ~ 1000V) and ground bond (AC 30A max.) tests, are performed under a high-stability voltage output with high-resolution measurement results. Further more, the test duration, ramp up time and upper/lower limits of the output voltage are fully-adjustable to accommodate a wide variety of safety tests with accurate measurement results.
 
Other functions and features of the GPT-9800 include: open circuit detection for ground bond testing to get correct measurement result with confidence; 100 sets of memory to save panel settings, which can be recalled for single test individually or for automatic tests in sequence; a remote output on-off terminal in the front panel and a signal I/O port in the rear panel provided as the means for remote start/stop control of the safety tester; RS-232C, USB and GPIB (optional) interfaces available for PC remote control and test result logging.

High Efficiency

PWM Amplifier Design

Unlike conventional safety tester design that uses variable voltage transformer and class A/B amplifier to provide test voltage, the GPT-9800 Series, carrying a high-efficiency PWM amplifier design, generates output source up to 98% efficiency. This greatly reduces the amount of power loss to heat and therefore lowers the temperature within the cabinet. The suppresion of temperature rise during heavy-duty

Operations of the tester significantly increases its reliability and service lifetime. In addition, as PWM amplifier is comparatively more resistant to the fluctuations of input power voltage, a stable high-voltage output with less than 1% regulation is provided by the GPT-9800 Series to perform precision tests.

Step Adjustment

In order to provide high accuracy safety test for product manufacturing, regulation compliance, and characteristics verification, the withstanding test voltage (AC 5kV Max./DC 6kV Max.) of the GPT-9800 Series can be adjusted in 2V steps, while the current measurement can be done with 1µA resolution and ±(1.5% + 30µA) accuracy to enable small leakage current measurements of the products of the components. In addition, the test voltage of insulation resistance of the GPT-9800 Series can be adjusted in 50V steps within its DC output range from 50V to 1000V, carrying a measurement accuracy of ±(10% of reading +1MΩ) at full scale (2000MΩ/9500MΩ). This provides the flexibility for performing I.R. measurements under variable levels of applied voltage.

As the Majority of safety regulations need an AC source for ground bond test, the GPT-9800 Series provides 6Vac voltage (open circuit) and 3A-30Aac current for ground bond test, meeting IEC 60601-1 requirements. Furthermore, open circuit detection (via SOURCE H, SENSE H and SOURCE L terminals) for ground bond testing is also provided to check if the test apparatus has been properly connected before the start of a test. This is to ensure the ground bond test is done accurately without any unnoticeable misconnection between the test leads and the test terminals. With these capabilities, the user is able to perform various safety tests and verifications with high flexibility, accuracy and confidence.

Safety Guarding

Self Check

To protect operator from high voltage shock and DUT from unintended damage, the protection functions are always in operation throughout the testing period. When the power is turned on, the GPT-9800 Series immediately goes through the self-check procedures to ensure that all test functions are performed under normal conditions, as the first protection function being applied.

The second protection function is activated once the "Start" (output) button is pressed. Within the 100ms initialization period of output start, the GPT-9800 will send a detection voltage (-100V) to check whether the DUT has any short circuit defect due to poor insulation before the high voltage is applied. This is to prevent high voltage or current from returning to the DUT during the test time. To protect DUT from insulation breakdown caused by the rapid increase of test voltage at output starts, and avoid flashover or arcing phenomena that could affect the test results, the GPT-9800 Series has a Zero Crossing Turn-On feature, which ensures the output voltage to always start from the zero crossing of a sine wave. Moreover, the adjustable voltage ramp-up time (0.1s~999.9s) allows the test voltage to slowly rise to the set test voltage to reduce the risk of damaging DUT during mandatory production testing.

Continuous Monitoring

Furthermore, after the voltage has ramped to the set test voltage, the GPT-9804 will continue monitoring the test voltage and cut off power output once any irregularity is detected. This provides both the safety tester and the operator with a high level protection, which allows the test to be done in a safe and accurate manner.

Other Protection Mechanisms

The GPT-9800 Series also offers a variety of features for personnel protection to ensure operator's safety when operating the safety tester. The interlock function is provided to set double-start operation procedures for high voltage output. When the interlock function is activated, a dedicated interlock key must be inserted into the the Signal I/O port for the tester to start sending out test voltage. This mechanism is designed to prevent unauthorized person from getting access to the tester; the safety tester operator only needs to remove the interlock key to disable the tester output before leaving the working environment.

The interlock I/O can also be connected to an external safety device, such as a senor switch or the safety door of a test fixture, to provide "double start" protection. This additional output on/off switch disables the output before the external safety device is activated and thus prevent operator from the exposure of hazardous voltages/currents. In addition, the GPT-9800 Series can quickly cut off its high voltage output within 150µs after the test has been completed, or the high/low current limit has been reached, or an abnormal situation occurs. When a test is completed, the unit will automatically discharge the DUT within 200ms to reduce the hazardous risk of the operator in case of an inadvertent touch of the test apparatus.