In summary, the GW Instek GPT-9804 is a benchtop electrical safety tester that performs AC withstanding, DC withstanding, insulation resistance, and ground bond continuity testing in a single 4-in-1 instrument. It is built on a high-efficiency PWM amplifier platform delivering 200 VA of AC output capacity, with high-resolution measurement (1µA current resolution, 2V voltage steps) and a 240 × 64 dot-matrix LCD for clear readout of conditions, parameters, and results. The instrument is designed to meet the test requirements of IEC, EN, UL, CSA, GB, JIS, and other safety standards applied to electrical products and components.
What is the GW Instek GPT-9804 used for?
The GPT-9804 is used for production-line safety testing, quality-assurance verification, and safety-standard compliance pre-qualification of electrical products. Typical devices under test include power cords, home appliances, information technology equipment, and medical equipment. Operators apply the tester at the manufacturing, regulation-compliance, and R&D stages to confirm that insulation barriers between live circuits and accessible surfaces are intact and that protective earth connections are reliable under fault current.
Which safety tests does the GPT-9804 perform?
It is a 4-in-1 model capable of AC withstanding, DC withstanding, insulation resistance, and ground bond continuity testing. Ground bond is measured at high test current (up to 30 A AC) using a four-terminal Kelvin connection, with open-circuit detection (via SOURCE H, SENSE H, and SOURCE L terminals) to verify proper test-lead connection before the test starts. All major test functions are performed under high-stability voltage output with high-resolution measurement results. Test duration, ramp-up time, and upper/lower limits are fully adjustable to accommodate a wide variety of safety tests.
The GPT-9804 delivers the following measurable performance against datasheet specifications: AC withstanding 0.100–5.000 kV at 200 VA, 40 mA max, 2V resolution, ±(1% of setting + 5V) accuracy; DC withstanding 0.100–6.000 kV, 10 mA max, 0.001 mA best resolution, ±(1.5% of reading + 30 µA) current accuracy; IR test 50–1000 V DC across 1 MΩ to 9500 MΩ range; Ground bond 3–30 A AC, 0.1 mΩ to 650 mΩ range at 0.1 mΩ resolution; Ramp time 0.1–999.9 s, test time off or 0.5–999.9 s, automatic DUT discharge within 200 ms; 100 MANU memory blocks plus 100 AUTO memory blocks with up to 16 steps per AUTO sequence. Output regulation is held to less than 1% under load variation, and the PWM amplifier topology achieves up to 98% efficiency — reducing internal heating and improving service lifetime compared to conventional transformer + class A/B designs.
The GPT-9804 addresses the electrical-safety regulatory framework that governs mains-connected products in global markets. The instrument is designed to support testing to IEC 60601-1 (medical electrical equipment), IEC 60335 (household appliances), IEC 62368-1 and IEC 60950 (information technology and audio/video equipment), and the corresponding UL, CSA, EN, GB, and JIS derivatives applied at certification and in production. GW Instek (Good Will Instrument Co., Ltd., established 1975, Taipei) is a global supplier of test and measurement instruments distributed through authorized partners worldwide.
Common applications
- Full-coverage safety analysis for IEC 60601, IEC 62368, and IEC 60335 product certification
- Production lines combining hipot, IR, and ground bond in a single test station
- Contract manufacturers running 100% safety screening on every unit shipped
Accessories Supplied
The GPT-9804 ships from the factory with the following standard accessories:
| Item |
Qty |
| Quick Start Guide |
1 |
| Power cord |
1 |
| CD (complete user manual) |
1 |
| Interlock key |
1 |
| Remote terminal male plug |
1 |
| Test lead GHT-114 |
1 |
| Test lead GTL-115 |
1 |
Optional Accessories
| Part Number |
Description |
| Opt.1 |
GPIB card |
| GHT-113 |
High Voltage Test Pistol |
| GHT-205 |
High Voltage Test Probe |
| GTL-232 |
RS-232C cable, 9-pin female to 9-pin null modem, for computer |
| GTL-247 |
USB cable, A-A type, approx. 1.8 m |
| GTL-248 |
GPIB cable, approx. 2 m |
| GRA-402 |
Rack adapter panel (19", 4U) |
Product Core & Specifications
The GPT-9804 is built on a high-efficiency PWM amplifier platform with up to 98% efficiency, reducing internal heat versus conventional variable-transformer + class A/B designs. Output regulation stays under 1%. Hardware and software protections include power-on self-check, zero-crossing turn-on, output cutoff within 150µs of an abnormal condition, automatic DUT discharge within 200 ms, and a hardware safety interlock.
After "Start" is pressed, a 100 ms initialization applies ~100V to detect short-circuit defects before full test voltage ramps up. The 240 × 64 Ice Blue LCD displays conditions, parameters, measurement values, and pass/fail simultaneously, with multi-color status LEDs that flash whenever output voltage is present.
AC Withstanding Specifications
| Output Voltage Range |
0.100kV – 5.000kV ac |
| Output Voltage Resolution |
2V/step |
| Output Voltage Accuracy |
±(1% of setting + 5V) [no load] |
| Maximum Rated Load |
200 VA (5kV/40mA) |
| Maximum Rated Current |
40mA (0.5kV
|
| Output Voltage Waveform |
Sine wave |
| Output Voltage Frequency |
50Hz / 60Hz selectable |
| Voltage Regulation |
±(1% of reading + 5V) [full load → no load] |
| Voltmeter Accuracy |
±(1% of reading + 5V) |
| Current Measurement Range |
0.001mA – 40.0mA |
| Current Best Resolution |
0.001mA / 0.01mA / 0.1mA |
| Current Measurement Accuracy |
±(1.5% of reading + 30µA) |
| Window Comparator Method |
Yes |
| ARC Detect |
Yes |
| RAMP (Ramp-Up Time) |
0.1s – 999.9s |
| TIMER (Test Time) |
OFF, 0.5s – 999.9s |
| GND |
RETURN / GUARD |
DC Withstanding Specifications
| Output Voltage Range |
0.100kV – 6.000kV dc |
| Output Voltage Resolution |
2V/step |
| Output Voltage Accuracy |
±(1% of setting + 5V) [no load] |
| Maximum Rated Load |
50W (5kV/10mA) |
| Maximum Rated Current |
10mA (0.5kV
|
| Voltage Regulation |
±(1% of reading + 5V) [full load → no load] |
| Voltmeter Accuracy |
±(1% of reading + 5V) |
| Current Measurement Range |
0.001mA – 10.0mA |
| Current Best Resolution |
0.001mA / 0.01mA / 0.1mA |
| Current Measurement Accuracy |
±(1.5% of reading + 30µA) |
| Window Comparator Method |
Yes |
| ARC Detect |
Yes |
| RAMP (Ramp-Up Time) |
0.1s – 999.9s |
| TIMER (Test Time) |
OFF, 0.5s – 999.9s |
| GND |
RETURN / GUARD |
Insulation Resistance Specifications
| Output Voltage |
50V – 1000V dc |
| Output Voltage Resolution |
50V/step |
| Output Voltage Accuracy |
±(1% of setting + 5V) |
| Resistance Measurement Range |
1 MΩ – 9500 MΩ |
| Resistance Measurement Accuracy |
±(5% of reading + 1 MΩ) in the principal range; ±(10% of reading + 1 MΩ) in the extended high-resistance range. Full accuracy matrix by test voltage and measurable range is published in the Manufacturer's Data Sheet. |
| Window Comparator Method |
Yes |
| RAMP (Ramp-Up Time) |
0.1s – 999.9s |
| TIMER (Test Time) |
1s – 999.9s |
| GND |
GUARD (fix) |
Ground Bond Specifications
| Output Current |
03.00A – 30.00A ac |
| Output Current Resolution |
0.01A |
| Output Current Accuracy |
3A≤I≤8A: ±(1% of reading + 0.2A); 8A
|
| Test Voltage |
6 Vac max (open circuit) |
| Test Voltage Frequency |
50Hz / 60Hz selectable |
| Resistance Measurement Range |
0.1 mΩ – 650.0 mΩ |
| Resistance Measurement Resolution |
0.1 mΩ |
| Resistance Measurement Accuracy |
±(1% of reading + 2 mΩ) |
| Window Comparator Method |
Yes |
| TIMER (Test Time) |
0.5s – 999.9s |
| Test Method |
Four Terminal |
Note on probes & accessories: The optional GHT-113 High Voltage Test Pistol and GHT-205 High Voltage Test Probe support manual contact testing of larger assemblies. Probe choice depends on fixture geometry, voltage range, and operator-safety procedures — consult your Test Architect to match the right accessory to the application.
Important — high-voltage safety: The GPT-9804 produces lethal voltages at its output terminals during testing. The hardware interlock key must be installed in the Signal I/O port for the tester to send high voltage; never bypass it. Calibration documentation is available as an optional service where formal accredited testing requires NIST-traceable verification.
General & Interface Specifications
| Memory — Single Step (MANU) |
100 blocks |
| Memory — Automatic Testing (AUTO) |
100 blocks, menu per auto: 16 |
| Interface — RS-232C |
Standard |
| Interface — USB |
Standard |
| Interface — GPIB |
Option |
| Remote Terminal (Front) |
Standard |
| Signal I/O |
Standard |
| Display |
240 × 64 Ice Blue dot-matrix LCD |
| Power Source |
AC 100V / 120V / 220V / 230V ±10%, 50/60Hz |
| Dimensions (W × H × D) |
330 × 150 × 460 mm |
| Weight |
Approx. 19kg max. |
This webpage was written by a human with an A.I. "Intern", which may contain errors. Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.