ATEquip.com is a subsidiary of Vitrek Corp. and is an authorized distributor of GW Instek Test Equipment.
GW Instek GPT-800 Series Hipot Testers 500VA
The GPT/GPI-800 Electrical Safety Testers (EST) are Hipot Testers designed for
AC/DC Withstanding Voltage testing and Insulation Resistance (IR) testing to provide electrical safety compliance testing and certification to JIS, CSA, UL,
BS, EN, etc.
Traditionally, 'Hipot' is a term given to a class of electrical safety testing instruments used to verify electrical insulation in finished appliances, cables or other wired assemblies, printed circuit boards, electric motors, and transformers. A Hipot test (also called a Dielectric Withstand test) verifies that the insulation of a product or component (also referred to as the dielectric) is sufficient enough to protect the operator from electrical shock. In a typical Hipot test, high voltage is applied between a product's current-carrying conductors and its metallic chassis. The resulting current that flows through the insulation, known as leakage current, is monitored by the tester. The theory behind the test is that if a deliberate over-application of test voltage does not cause the insulation to break down, the product will be safe to use under normal operating conditions -- hence the name, Dielectic Withstand test.
In addition to over-stressing the insulation, the test can also be performed to detect material and workmanship defects, most importantly small gap spacings between current-carrying conductors and earth ground. When a product is operated under normal conditions, environmental factors such as humidity, dirt, vibration, shock and contaminants can close these small gaps and allow current to flow. This condition can create a shock hazard if the defects are not corrected at the factory. No other test can uncover this type of defect as well as the Dielectric Withstand test. The Instek GPT/GPI-800 Electrical Safety Testers were designed for are ideal for conducting these types of tests.
Three types of Hipot tests are commonly used. These three tests differ in the amount of voltage applied and the amount (or nature) of acceptable current flow:
Dielectric breakdown Test
The test voltage is increased until the dielectric fails, or breaks down, allowing too much current to flow. The dielectric is often destroyed by this test so this test is used on a random sample basis. This test allows designers to estimate the breakdown voltage of a product's design. The Instek GPT-805 and GPT-815 are ideal for and were designed to satisfy this type of testing requirement. The GPT-815 features both AC and DC testing capability while the GPT-805 is an AV only testing instrument.
Dielectric Withstand Test
A standard test voltage is applied (below the established Breakdown Voltage) and the resulting leakage current is monitored. The leakage current must be below a preset limit or the test is considered to have failed. This test is non-destructive and is usually required by safety agencies to be performed as a 100% production line test on all products before they leave the factory. The Instek GPT-805 and GPT-815 are ideal for and were designed to satisfy this type of testing requirement. The GPT-815 features both AC and DC testing capability while the GPT-805 is an AV only testing instrument.
Insulation Resistance Test
This test is used to provide a quantifiable resistance value for all of a product's insulation. The test voltage is applied in the same fashion as a standard Hipot test, but is specified to be Direct Current (DC). The voltage and measured resulting current value are used to calculate the resistance of the insulation. The Instel GPI-825 & GPI-826 are ideal for and were designed to satisfy this type of testing requirement.
Instek GPT-805/GPT-815/GPI-825-GPI-826 Series
Abbreviated Specifications:
AC Withstand: AC Test Voltage 0.2~5KV
DC Withstand: DC Test Voltage 0.2~ 5KV (GPT-815 Only)
IR Testing: DC Test Voltage 500VDC & 1000VDC (GPI-825 & GPI-826)
Test Time: Continual and 1 to 180 seconds
Arc Detection: GPT-805 (0.3~10mA); GPT-815 (0.3~100mA AC& DC); GPT-825 (0.3~100mA AC); GPI-826 (0.3~20mA AC)
Remote Control: via Rear Panel Terminal
Output Monitor: 3½ Digit Display Voltage and Current
Test Timer: 3 Digit Display
Featuring:
- 500VA AC Test Capacity
- True RMS Current Read-out
- Arc Detection
- Zero Turn-On Operating Switch
- 3 Ranges of Adjustable Cut Off Current
- Digital Display for Voltage, Current and Timer at Same Time
- Automatic FAIL Indicator of Alarm Lamp and Buzzer
- 9 Pin Remote Control for START, RESET
- Current and output voltage setting
- Easily and quickly setting with front panel control
- Testing time controlled by microprocessor design.
- Adjustable ARC detect level
- Adjustable output voltage during test
- An alert indicator for high voltage
- Remote I/O controlled
Budgetary Guidance: $600~$700
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GW Instek GCT-630 Ground Bond Tester
Ground Bond Testing
A ground bond test is conducted to verify the integrity of the ground path of the Device Under Test (DUT) by applying a high-current, low-voltage source to the ground-path circuit. It is also known as the ground bond continuity test. The ground bond test must be conducted on all Class I products. The purpose of the test is to ensure that all accessible conductive parts of the DUT that could become live in the event of a single insulation fault are connected securely to the final earth point of the supply input. In other words,
Compliance is checked by measuring the resistance of the connection between the protective earth-connection terminal or earth contact and the parts to be earth-connected to ensure that resistance does not exceed certain specified values when subjected to a high current as specified in various product safety standards. It is important to bear in mind that from the constructional and design points of view, the protective earthing conductors should not contain switches or fuses.
Test Requirements
Most safety standards require the following parameters for conducting the ground bond tests:
- The DUT must be subjected to a high AC or DC current with a low test voltage for a certain period of time.
- The voltage drop between the protective earth terminal
or earth contact and the part to be earthed must be measured.
- Using Ohm's law, the resistance must be calculated from the current and the resulting voltage drop.
The resistance should not exceed specified values as stated in the various safety standards, e.g., IEC 60950 requires that the test voltage not exceed 12 V. The current can be either ac or dc at 1.5 times the current consumption of the product or 25 A, whichever is greatest. The test duration must be 1 minute, and the resistance of the connection between the protective earth-connection terminal or earth contact and parts required to be connected to earth must not exceed 0.1 Ω. This value does not include the resistance of the power cable. Some standards, such as CAN/CSA-C22.2 No. 60950-00 or UL 60950 with Canadian deviations, require the test to be conducted at 30 A for 2 minutes if the current rating of the circuit under test is 16 A or lower.
Understanding Resistance Values
With the exception of the Canadian standard, most standards require 25 A for 1 minute. The value of 25 A for 1 minute represents the worst current and the longest operation time of a mains over-current protection device. The maximum 25 A is approximately 1.5 times the mains' circuit breaker value installed for most pluggable type A cord-connected equipment rated up to 16 A. The Canadian National Wiring Code requirements are very similar to these in the sense that they assume that fuses are expected to operate for no more than 1 minute at twice their rated current. Because most mains circuits are protected with a 15–16 amp fuse, the fault current would be 30 A for no more than 2 minutes.
Instek GCT-630 Ground Bond Tester
The performance and features of the GW Instek GCT-630 Ground Bond Tester are designed to provide up to 32 amps with a compliance voltage of 8VAC to test the integrity of the ground bond resistance of electrical products connected the AC power mains. The resulting resistance is measured and displayed. Test parameters may be set and the results gauged to be Go/No-Go to remove operator decision making from the test program.
Abbreviated Specifications:
Test Current: 3A~32A AC
OCL: 35A AC ±5% Maximum
Test Voltage: 8V AC typical
Resistance Range: 0~0.12Ω and 0~0.6 Ω (2 ranges)
Accuracy: ±5% from 5A to 32A AC
Current Monitor: 0~32A AC (±5% F.S.)
Go/No-Go Current Setting: 5% to 100% of Range
Remote Control: Hi-Lo Voltage Signals (applied externally)
Output Monitors: Analog Meters
FEATURES：
- Test Ground Continuity Resistance
- AC 32 Amperes High Test Current
- Measuring Resistance from 0 ~ 0.6Ω
- 8VAC Compliance
- Continue & Normal test mode
- Four wire measurement
- Remote Control
- GO/NO-GO function or Pass/Fail
- Test and Result output signal
Budgetary Guidance: Under $1500
ATEquip.com is a subsidiary of Vitrek Corp. and is an authorized distributor of GW Instek Test Equipment.
