Proving Units
An essential accompaniment to a voltage tester, proving units verify that the tester remains accurate both before and after testing. Both the NICEIC and NAPIT strongly recommend using these regularly when testing.
Find out more about Proving Units below.
- Test the functionality of non-contact voltage testers before and after use
- Indicates functionality via a visual LED alert
- Rugged design, drop tested from 1m
- Compact and lightweight
- Suitable for proving high and low impedance instruments
- Inbuilt 200kΩ load limits the current to 3.5mA at 690V
- Single voltage output: 690V AC
- Applies full voltage upon contact
- Auto Power Off function
- Long battery life
- Maximum output current of 2mA
- Maximum output voltage of 240V
- Compact body made from flame-retardant ABS for safety
- Simple Design
- Robust Casing
- Magnet within the base
- 5 stepped nominal output voltages
- Automatic operation
- High output power suitable for test lamps
- Step voltage indication
- First proving unit to generate an AC voltage waveform
- Compact design
- 3 ranges
- Switchable AC / DC output mode
- Suitable for use with voltage indicators up to 230V
- Auto Power Off
- Lightweight, compact, and rugged
- Long battery life
- Low battery indicator
- Compact and lightweight voltage-proving unit
- AC output up to 690V
- High- and low-Z impedance compatibility
- Verify the functionality of multimeters, two-pole voltage indicators and non-contact voltage detectors
- Intelligent voltage ramp: 50V, 100V, 230V, 400V and 690V
- Able to synthesise tests at an AC mains supply frequency
- Stepped voltages
- CALCHECK
- Auto Power Off function
- Low battery indicator
- CALCHECK
- Low battery indicator
- Long battery life
- Auto Power Off function
- Bespoke pouch means the kit can be carried on the user’s person
- Three-in-one voltage, continuity and phase tester
- Proving unit for maintaining compliance with safe isolation procedures
- 4 ranges
- Switchable AC / DC output mode
- Suitable for use with voltage indicators up to 440V
- CALCHECK
- 4 ranges
- Compatible with S-series magnetic hanger
- Bespoke pouch means the kit can be carried on the user’s person
- Three-in-one voltage, continuity and phase indicator
- Proving unit suitable for testing high and low impedance instruments
- 5 ranges
- Switchable AC / DC output mode
- Suitable for use with voltage indicators up to 690V
- Low-profile, durable proving unit
- 690V test voltage
- Heavy denier nylon case with a shoulder strap and clear front pocket
- Performs TBT tests
- Simple-to-use single switch operation system
- Protects the user from risks of shock and arc flash
- LED lights for functionality indication
- Generates both AC/DC voltage to 240V
- LED indicator
- Ideal for use with clamp meters and multimeters, as well as two-pole voltage testers
- PD440S: 440V industry-leading proving unit
- VI13800 Voltage tester range: 50V to 600V AC/DC
- TC71 Combination Carry Case
- KANE-VCT Voltage Tester
- KANE-PU690V Proving Unit
- Kit Carry Pouch
- Batteries
- Ultimate solution for safety isolation procedures
- The KEWLOK padlock small size fits perfectly in pockets or tool kits
- KEWPROVE 3 works directly with the KT1795
About Proving Units
Proving units are portable, lightweight calibration tools that are designed for use with two-pole voltage testers. The function of a proving unit is to evaluate that the internal components of the voltage tester are working correctly and that measurement accuracy is maintained.
Although regular, formal calibration is still a priority, using a proving unit in combination with a two-pole voltage tester is an ideal way to ensure measurement accuracy is maintained in the period between official calibration procedures. Most manufacturers recommend that a proving unit is used both before and after testing using a voltage tester; this way, damage to the machine during transportation can be detected before testing, or damage to the machine during the actual testing procedure can be detected afterward.
Proving units come in many different forms to accommodate the vast voltage range spectrum that can be applied to two-pole testers. Some proving units might be designed for measuring low voltage testers, while others may be designed for higher voltage. Some may also be suitable for both low and high-voltage testers, measuring across the entire spectrum. A common function found on these units is ramp voltage. The proving unit applies several different voltages to the two-pole voltage tester that is inserted into ports on the proving unit and the device measures whether everything is working correctly with the applied voltage. The indicators are usually expressed via the use of LED lights and if everything is correct the LED light indicators should tell you that this is the case.
Stepped voltages again vary depending on the proving unit being used.
Using a proving unit to maintain accuracy is particularly important as frequent usage of a tester can result in the compromise of measurement accuracy. Other factors such as knocks and bumps, dust, water, and other forms of natural contaminants can also affect the accuracy of a tester over time and if these inaccuracies go unnoticed it can make the tester unsafe and also produce incorrect readings when used on a system.
Our range of proving units come from many different manufacturers, including Kewtech, Martindale, Megger, Seaward, and Socket and See. As mentioned earlier their capabilities vary from tester to tester, so knowing which unit you need before making a purchase is highly recommended. If you're confused about which unit you need we're more than happy to help you make a decision - get in touch and we'll help you out choosing the right proving unit for use with your voltage tester.
