Vitrek Hipot and Electrical Safety Testers

Introduction to Hipot Testing

What is Hipot Testing?

The term "hipot test" is short for high potential (high voltage) test and is also known as dielectric withstand testing. A hipot test checks for "sufficient insulation and isolation between Line and Neutral to Ground".

Hipot testers produce high potential to perform dielectric withstand and insulation resistance tests. In addition to these tests, many hipot testers provide accurate low-resistance measurements and low-resistance/high-current outputs to test ground resistance and ground bond integrity. Hipot testing has long been a standard procedure for assuring the electrical safety of electronic equipment.

Why is Hipot Testing Important?

Hipot testing is critical in assuring compliance with a host of electrical safety standards and in confirming the assembled product is free from electrical or mechanical defects. Hipot testers are used to measure leakage current and insulation resistance between all components and connections, confirming solid ground connections and test ground bonds. All these tests require the sequential application of precise and controlled high voltages or currents between pairs of elements then accurately measuring and recording the results. Products like the Vitrek 95x and V7x series are excellent examples of the industry’s best electrical safety testers.

Key Application: Electrical Safety for Appliance & Consumer Product Manufacturers

Electrical appliances, computers and peripherals, power tools and other devices found in the home and office environments must be tested to confirm adherence to a plethora of stringent certification standards.

The vast array of consumer devices for the home and office — from blenders and ovens to computers and high-definition LED TVs — are becoming increasingly sophisticated. Refrigerators, once basic electrical appliances, now often include adjustable speed motor controls, digital displays and Bluetooth communications.

While the complexity and functionality found in this class of devices varies extensively, there is one thing they all have in common when products enter the market: proven safety compliance. It is a foregone expectation that electrical and electronic devices designed for consumer environments will have been tested and labeled as compliant according to applicable safety standards, which means bearing the mark of a Nationally Recognized Testing Agency (NRTL).

Many safety requirements are confirmed, both in the design stage as well as in production, using electrical safety (hipot) testers. Vitrek’s line of electrical safety testers are ideal choices for this application.

How Does a Hipot Test Work?

The basic hipot test applies a high voltage from the conductors to the chassis of the device-under-test (DUT). This test is often referred to as a "dielectric" or "voltage" withstand. Its purpose is to confirm that the insulation and isolation of the non-conducting surfaces from the operating voltage is sufficient to avoid a shock hazard. The typical specification for this test ins 1000V + 2 x normal operating voltage.

Both AC and DC hipot tests are possible and, in general, the test should use the same type of voltage as it would be during normal operation. However, if a DC hipot test is used on an AC circuit, the hipot voltage should be two times the peak (2 x 1.4 x RMS) + 1000V

Depending on the applicable standard, units pass this test if either:

The leakage current measured is less than the maximum allowable current
No breakdown occurs, i.e., no sudden and uncontrolled flow of current

Four double-insulated products, higher voltages will often be specified in the test standard. In addition, this class of device typically requires special fixturing to connect the non-conductive outer shell to a conductive element.

Defects that are often detected with the hipot test include contamination (dirt, debris) and lack of proper spacing (creepage and clearance) of components. Creepage is measured across surfaces, clearance is the air gap between components. Contamination would likely cause an unacceptable level of leakage current. Clearance problems could result in breakdown.

Product Safety Certification

Electrical safety testing and certification is a requirement for virtually every electronic device and electrical apparatus. The details of what constitutes a certified product is dependent upon a daunting number (hundreds) of safety standards and the region of the world where the device will be sold and used. Standards setting organizations include:

EN/IEC (European)
UL (US)
CCC (China)
CSA (Canada)
JEIDA/MITI (Japan)

Manufacturers must submit samples of their products to recognized certification agencies. Nationally Recognized Certification Laboratories (NRTLs) include UL, VDE, FM, ETL and others. The agency certification process is conducted to confirm compliance with the relevant standard(s). This compliance evaluation investigates two key areas:

Construction – Mechanical construction, spacing, clearances, etc.
Safety – To assure safe operation (even under high-stress conditions)

Work is being done to harmonize standards from global agencies. For example:

The IEC 61800-5-1 is a safety standard specified by the International Electrotechnical Commission for adjustable-speed electrical power drive systems. It covers the safety aspects related to electrical, thermal and energy. The former UL standard (UL508C) has now been supplanted by new standard, harmonized with the IEC requirements.
The UL document announcing this change put it this way: "This harmonization work was undertaken with the intent of creating a standard that, while being based upon and adopting IEC requirements, would incorporate national differences that would address US installation requirements (NFPA 70, US National Electrical Code). This goal has largely been accomplished in all cases."

To further help manufacturers address this often-bewildering array of international (and sometimes conflicting) standards, the Power Sources Manufacturers Association (PSMA) has established a standing committee and forum on its website.

Production Electrical Safety Testing

Electrical safety testing is an important final step in the production process for most electrical and electronic equipment to:

Assure compliance safety agency labeling requirements
Detect defective components or assembly flaws
Reduce incidence of latent field failures and the attendant warranty costs

Once in production, products must be 100% tested to confirm with the related agency certifications and safety standards. Production tests are less stringent than initial certification but will generally include basic dielectric withstand and shock hazard (leakage) tests. Plug-connected devices will also be subjected to ground resistance and (if the standard requires) ground bond tests. Electrical motors, transformers and other such devices will likely include insulation resistance tests.

Periodic inspection and calibration of test equipment is a standard requirement to maintain NRTL certification. Agency inspection will include check of hipot instrument calibration. This “cal cert” is typically required on an annual basis. (UL and other NRTLs require compliance certification with ISO17025.) Another common requirement prescribed by most NRTLs is a daily functional test of the hipot equipment.

The Vitrek Difference for Hipot Testing

Vitrek hipot testers serve a range of different industries and are designed by experts who have made the company a global leader for supporting electrical safety tests. Each series of hipot testers is designed to handle AC and DC hipot, while select models can also measure IR insulation resistance. Vitrek manufactures two different series of hipot and electrical safety testers. These hipot testers have been designed to fit your testing application. Each series offers 6 different models with a wide variety of electrical safety test functions and capabilities.

Vitrek's hipot testers all come standard with a variety of computer interfaces to simplify test automation right out of the box, and they can be used with Vitrek’s QuickTest Pro software. Combine the Hipot safety testers with one of Vitrek's High Voltage Switching Systems for a full multi-point hipot testing solution, all controlled through the tester. In addition, Vitrek’s Hipot and Electrical Safety Testers come with world class customer support – before, during and after the sale.

95X Series Ultra-High Performance Hipot Testers

Power & Versatility for Electrical Safety Test Applications

Vitrek built the 95X Series from the ground up with DSP technology – to bring you the safest, fastest, most capable, feature rich hipot testers available. The 95X Series combines high output power, with a wide range of AC & DC voltage outputs and extremely low leakage current measurement. Then Vitrek added a 4-wire milli-ohmmeter with dynamic range up to 100K ohms and an overlapping Tera-ohm class Insulation Resistance function. Top that off with an available 40 Amp Ground Bond capability and you are just beginning to get a feel for what the Vitrek 95X Series Hipot Testers can do for you.

For Demanding Hipot Tests – Demand the Vitrek 95X

Speed and power go hand in hand, the 6.5KVDC models offer 50mA of source current for DC Hipot – providing the power you need to rapidly charge and discharge challenging DUTs. Models are also available with DC hipot up to 11KV and 15KV. Most of the 95x series also offer 50mA of sourcing for AC hipot, but for heavier AC loads the 95X can be configured to source up to 100mA or even as much as 200mA. For higher AC hipot voltages the 95X can generate up to 10KV internally and all models are available with an external 30KVAC hipot option.

When it comes to making critical leakage current measurements, the 95X delivers rock-solid resolution down to 100 pico-amps. This high resolution provides built-in insulation resistance measurement (IR) up to a Tera-ohm, add a 4-wire milli-ohmmeter with auto-ranging up to 100K ohm and an available 40 amp Ground Bond function – and you are beginning to understand the versatility of the Vitrek 95X Series.

Need to Hipot Multiple Test Points?

The 95X can directly control up to four 64 channel HV scanners, right out of the box. That is up to 256 test points and using a PC with Vitrek’s QuickTest Pro software you can expand the count to 640 test points. The HV Switching System of choice is the Vitrek 964i, which can hold eight 8 channel switching cards – available in 7, 10 & 15 KV ratings. The 964i also has switching cards to handle routing up to 40 amp ground bond currents.

95X Series Output Comparison Chart

Capabilities	951i	952i	953i	954i	955i	957i	959i
AC Hipot (Max Std Current) (500VA Option) (2KV Max Option) (30KVAC Ext. opt)	20V-6KV 50mA 100mA 200mA 10mA	20V-6KV 50mA - 10mA	20V-6KV 50mA 100mA 200mA 10mA	20V-6KV 50mA – 200mA 10mA	50V-10KV 30mA – – 10mA	20V-6KV 50mA 100mA 200mA 10mA	– – – – –
DC Hipot / IR (Max Current (Max IR)	30V-6.5KV 50mA 4T	30V-6.5KV 50mA 4T	50V-11KV 30mA 8T	50V-11KV 30mA 8T	50V-11KV 30mA 8T	100V-15KV 10mA 10T	– – –
40A Ground Bond	–	Yes	–	Yes	–	–	Yes
4 Wire Ohmmeter 100µΩ to 149KΩ	Yes	Yes	Yes	Yes	Yes	Yes	Yes

95X Series Features and Benefits

Highest Level of Operator Safety –

GFI high speed shut down for earth ground leakage faults
SFI Safety Fault Interlock – High speed shut down output for interruption of safety interlock
TLSS Test Lead Safety Sense - Clamps DUT chassis near ground by continuously verifying connection of test leads

High Power Output – means better drive capability and increased test throughout. With up to 50mA of sourcing current for DC hipot, the 95X Series gets heavy duty jobs done fast – available 100mA & 200mA AC drive tackles even the toughest sourcing requirements.

Wide Range of built-in Voltage Capabilities – Choose from 6.5KVDC, 11KVDC or 15KVDC and 6KVAC, 10KVAC or up to 30KV RMS AC with external option

Expansive Test Sequence Memory – holds up to 100 tests with up to 100 steps per test. Tests can be selected via front panel, Ethernet, RS232, Digital I/O or with optional GPIB.

4-Wire Milli-Ohmmeter Function - Provides fast, accurate 5-digit resistance measurements with resolution down to 100µΩ and range up to 100K ohms

Ground Bond Test Capability – Available in three models with output currents from 100mA to 40Amps RMS and test times from 20mS to 1000 seconds or longer.

Fastest Hipot Testers available – Thanks to Dual Coldfire microprocessors combined with Dual DSPs to provide Ramp rates up to 50KV/second, dwell times as low as 20mS and overall test times as fast as 3mS in optional Flash mode.

Built-in Phase Angle Measurement - Allows the measurement and display of both resistive (in-phase) leakage current and reactive (out-of-phase) leakage current caused by capacitive coupling

Ethernet, RS232, Digital I/O, USB Printer & Scanner Control - All Standard Interfaces – Provides the highest level of test automation. GPIB optional

Ramp High/Dwell Low Current Limits - Permits the user to set separate limits for the ramp and dwell, providing faster ramp times and lower leakage test limits

Dual Dimensional / Test Specific / Broadband Arc Detection - The 95X Series utilizes time & amplitude-based arc limits and uniquely applies them to each desired test

Pico-Amp Leakage Measurement - Ensures that even the lowest leakage current levels are accurately detected and tera-ohm range IR readings are stable and precise

Continuously Variable IR Test Voltage - Unlike most IR testers which limit you to 3 or 4 discrete test voltages, the 950i Series allows you to select the test voltage you need. Starting as low as 20V all the way to 6.5KV, 11KV or 15KVDC

Capacitance Test Modes - For AC & DC hipot and IR provide tightly controlled charge and discharge profiles for superior results on critical solar panel tests and other highly capacitive loads

Lightweight Switching Power Supply Design - Better reliability, easier on your back. Compare the 8.2 kg 95X to whatever you have been using

Safety Tested per EN 61010-1. EMC compliant to EN 61326-1

V7X Series Compact and Rugged Hipot Testers

The Hipot Experience has been Redefined

The goal of the V7X series is to achieve the unheard of. To provide state-of-the-art performance in a powerful yet compact multi-function hipot tester—and do it at an entry level price. From an easy-to-use touch user interface, to its ultra-reliability, high efficiency, fan free design—the V7X provides unrivaled performance.

Electrical Safety Testing Will Never Be the Same

With color touch LCD and high-speed DSP technology, the compact and rugged V7X sets the standard for price/performance ratio. Made in the USA to meet tough UL, CSA, TUV and IEC Hipot requirements—the V7X provides unbeatable speed, accuracy, user safety and reliability.

Choose from six low-cost models offering AC and DC Hipot to 5KV, leakage current measurement to 100 nano-amps, Insulation Resistance to 450GΩ, Ground Bond to 30 amps and built-in switching. Combine all that with USB, RS232 and Digital I/O interfaces, plus a two-year warranty.

Test 8 DUTs at a Time with the V76

For multi-channel hipot testing—choose the V76 with 24 channels of built-in high voltage switching. With the versatile V76, you can test hipot or IR for any combination of up to eight test points and you can measure low resistance (from .001 ohm to 60K ohms) on up to eight conductors. All automatically with a single touch and all from a single compact tester. For requirements exceeding eight points, the V7X can control up to four Vitrek 964i 64 channel HV Switching Systems—providing up to 256 channels of Hipot test capability. Simple, fast, automatic multi-point hipot—make the switch to the Vitrek V7X. You will be glad you did.

V7X Series Test Functions

Capabilities	V70	V71	V73	V74	V76	V77	V79
AC Hipot	•	•	•	•	•	•
DC Hipot	•	•	•	•	•	•
IR		•	•	•	•	•
Ground Bond				•		•	•
Low Resistance	•	•	•	•	•	•	•
16 Ch HV Scanner					•

V7X Series Features and Benefits

Easy to operate with 4.3" color touch display & intuitive interface
Offers six functions to choose from: AC/DC hipot, IR, ground bond, continuity, built-in switching
Accurate and fast – 100mS min test time
5KV AC/DC hipot, 20mA max source current
Ground bond 1 to 30A RMS (42 A peak), 100µΩ resolution
100 nano-amps leakage current resolution
Multi-mode IR with steady/rising pass mode
USB 2.0, Serial/RS232 and digital I/O interfaces
Continuously variable insulation resistance to 450GΩ Max