Martindale Electric has completed its range of PAT (portable appliance tester) instruments with new top-of-range portable models, extending a portfolio the UK safety-test specialist has built around the requirements of the IET Code of Practice for In-service Inspection and Testing of Electrical Equipment.

The announcement, reported by Voltimum, is a line-up completion rather than a single flagship launch: the company now covers the PAT spectrum from entry-level handheld units to the new range-topping portables. Martindale has not yet published full specification sheets for the new instruments in the material available at the time of writing, so buyers should treat exact figures — earth-bond test current, insulation test voltage, load/run-test capability — as datasheet items to confirm with the vendor before committing.

What the move does signal is where the PAT market currently sits. In the UK, the legal driver is the Electricity at Work Regulations 1989, which place a duty on employers and duty-holders to maintain electrical equipment so that it remains safe. The IET's Code of Practice — now in its fifth edition — is the working document most contractors follow, and it defines the two pillars of the discipline: formal visual inspection and electrical testing. A competent PAT instrument has to cover both the measurable quantities (earth continuity, insulation resistance, and, for Class I equipment with a flexible cord, possibly touch current or substitute-leakage methods) and accommodate the pass/fail thresholds the Code sets out, which vary by equipment class and by the protective-conductor current limits applied.

The underlying physics is straightforward but threshold-sensitive. Earth-bond testing passes a test current — commonly 200 mA on "soft test" instruments, or up to 25 A on traditional high-current testers — through the protective conductor and measures resistance; the Code expects low-reading results, typically below 0.1 Ω plus a nominal allowance for the supply cord. Insulation resistance testing applies a DC voltage, normally 500 V between live conductors and accessible metalwork, and looks for values above 1 MΩ for Class I appliances and 2 MΩ for Class II. An instrument that cannot resolve these margins cleanly, or that applies the wrong test voltage to IT equipment, will generate false failures and wasted bench time. This is why range positioning matters: the top-of-range portables from any manufacturer typically add higher test currents, better resolution on low-resistance ranges, and memory or connectivity for record-keeping against the inspection regime.

Martindale's decision to complete the range also reflects a practical reality for test-equipment buyers. Contractors servicing mixed estates — offices with IT loads, workshops with Class I power tools, sites with 110 V distribution — either carry multiple instruments or specify one tester that spans all required test modes. A full-range portfolio lets a single vendor satisfy both ends of that decision, and shifts the competition onto calibration interval, serviceability, and the quality of the result storage and reporting software.

What the announcement does not yet establish is performance. Range-topping portables earn their position through measured, repeatable accuracy at the Code's thresholds, documented calibration traceability, and ergonomics that survive a working day on site — none of which can be judged from a line-up announcement. Buyers specifying against the fifth-edition Code should request the full datasheets, stated accuracy classes, and the calibration regime Martindale supports for the new models before standardising on them.

The open question the launch raises is one of adoption: with the range now complete, will Martindale's new portables displace the established high-current testers in contractor fleets, and does the company's calibration and service infrastructure scale to match? That, not the range architecture, is what a purchasing decision will turn on.