Best Voltage Tester UK: Two-Pole Testers And Proving Units For Electricians

The Electricity at Work Regulations 1989 require adequate precautions to prevent electrical equipment that has been made dead from becoming charged again during the work (regulation 13). HSE's FAQ adds that where work is on or near exposed conductors, they should be proven dead, using appropriate test equipment, before work starts. HSG85, HSE's safe working practices guidance, covers planning that work. HSE's FAQ says to isolate securely, apply a lock to each isolation device and post warning notices at the points of isolation. GS38 then asks you to prove the tester on the proving unit, test the circuit and prove the tester again.

GS38 (fourth edition, 2015) is the test-equipment guidance. The points that decide what you buy:

• Use the right detector (paragraph 19): to establish the presence or absence of voltage, use a proprietary test lamp or 2-pole voltage detector suitable for the working voltage, rather than a multimeter. HSE says incorrectly set multimeters and makeshift devices have often caused accidents.
• Prove the detector (paragraph 20): any device used to prove dead may fail to indicate danger, so prove it before and after use, preferably on a voltage proving unit. Some devices have built-in proving units. Otherwise use a known live source of similar voltage.
• Two-pole detectors (paragraph 12): a 2-pole voltage detector that conforms to BS EN 61243-3 does not need extra current-limiting resistors or HBC fuses.
• Non-contact sticks (paragraph 13): voltage sticks are for identifying live equipment, not for proving it dead. Only devices that make contact with the conductor should be used for proving dead.
• Probes (paragraph 9): leads and probes should be marked with their CAT rating and the maker's name, with finger barriers and no more than 4mm of exposed metal tip. HSE strongly recommends 2mm or less, or spring-loaded retractable screened probes.

Martindale VIPD138-S is a safe isolation kit: the VI13800 voltage indicator, a PD440S proving unit and a TC71 carry case. The page lists AC and DC indication in four stages from 50V to 400V, suitability for safe isolation procedures up to 600V, a CAT III 1000V and CAT IV 600V rating, and says it is GS38 compliant. The PD440S is described as a 440V AC proving device designed to enable voltage indicators to be fully checked. Listed features include retractable probes, heavy-duty finger guards and a cable with a white inner core that shows damage. The warranty is 2 years.

Martindale VT28PD-S is a VT28 two-pole voltage tester, a PD690S proving unit and a TC72 case. The page lists 12 to 690V AC/DC on the LED range and 10 to 690V on the combined LED and LCD range, continuity with a buzzer, phase rotation, a single-pole test and an LED torch. It states the kit fully meets the requirements of GS38 and proving dead procedures, with a CAT III 1000V and CAT IV 600V rating and a 2-year warranty.

The proving unit checks the indicator, not the circuit. That is the before-and-after proving step GS38 paragraph 20 asks for.

Fluke T150 is a two-pole voltage and continuity tester. Fluke's page lists 6 to 690V AC/DC, a CAT IV 600V and CAT III 690V safety rating, continuity from 0 to 400 kilohms and resistance up to 1999 ohms. Voltage is shown by LED, LCD, audible tone or tactile feedback. It weighs 180g and carries a 2-year warranty.

Fluke says it is designed according to IEC EN 61243-3:2014 to verify the absence of voltage, even with discharged batteries. GS38 refers to BS EN 61243-3 for 2-pole detectors. The Fluke UK page does not mention GS38 by name or list a proving unit, so pair it with a separate proving unit and check the tip protection you will use against GS38 paragraph 9.

Martindale NC2 detects AC voltage between 200V and 1000V at 40 to 400Hz, with a red LED at the tip, a buzzer and an LED torch. It is optimised for 230V single and 3-phase supplies. The page describes detecting the presence of voltage and does not claim it proves a circuit dead.

That matches GS38, which says non-contact or proximity detectors can be useful for indicating that something is live, for example when removing one cable from trunking holding many, but only contact devices should be used for proving dead.

• Two-pole voltage tester: detects voltage for safe isolation. It is the tool GS38 names for proving dead, used with a proving unit.
• Multimeter: measures voltage, current and resistance. GS38 notes that unsuitable leads, a wrong function setting or a voltage above the meter's limit can cause arcing, and recommends fused leads (usually not exceeding 500mA, HBC) when a multimeter is used.
• Continuity function on a two-pole tester: a quick check on a dead circuit. The Fluke T150 page lists continuity to 400 kilohms and resistance to 1999 ohms, and the Martindale VT28 lists a continuity buzzer. These pages describe voltage and continuity testers, not multifunction installation testers.
• Fused leads and resistance: GS38 warns that low-current fuses can add up to 2 ohms to a test lead, which matters when you use fused leads with resistance measuring equipment.

• Two-pole, with a proving unit: a kit that includes the proving unit saves buying one separately.
• Standard: GS38 refers to BS EN 61243-3 for 2-pole detectors. Check the maker's page names it, or says GS38 compliant.
• Category rating: the rating should suit the supply you work on. The Martindale and Fluke testers above list CAT IV 600V.
• Voltage range: confirm the range covers the supply. The VI13800 indicates 50V to 400V in four stages.
• Probe tips: no more than 4mm exposed, ideally 2mm or less or retractable.
• Prove before and after every use: a faulty tester can fail to indicate danger, which is why GS38 asks you to prove it.

For the rest of the kit, see the essential electrician tools guide and the best torque screwdriver for electricians. For the legal side, see the health and safety guide for electrician businesses.