Cable Testers
A cable tester identifies, traces, or verifies an electrical, telephone, or data cable without physically tracing it through walls, ducting, or bundled wiring. Ecotao supplies the Extech range of tone-generator wire tracers, non-contact cable locators, and continuity testers used by electricians, alarm and telecom installers, and facilities teams across South Africa to identify unmarked wiring, confirm circuit continuity, and locate hidden cables before drilling, cutting, or rewiring.
How to choose the right cable tester
- Identifying one wire in a bundle of unmarked cables? A tone generator and probe kit (TG20 or 40180) injects a signal you can follow with a hand-held probe — the fastest way to label individual wires or trace a cable's path along an accessible run.
- Locating a cable hidden inside a wall, ceiling, or floor? A non-contact cable locator (CLT600) is built for this — it detects the cable itself, powered or unpowered, so you know exactly where it runs before you drill or cut.
- Confirming a long run is unbroken, or labelling wires from a different room? A remote and local continuity tester (CT20) drives a signal through the circuit to a bi-colour probe at the far end, working over runs up to 3,000 metres.
- Working on a live or potentially energised circuit? Only use a tool with a CAT-rated safety voltage sensing, such as the CLT600 (CAT III-450V). Tone generators and continuity testers in this range are for unpowered, low-voltage telecom and data cabling only.
Our Cable Tester Range
Ecotao supplies the current Extech Cable Tracers and Continuity Testers lineup below. These replace older Extech models (CT40 and CT100) that have since been discontinued by the manufacturer — the four tools below are Extech's current equivalents, covering the same identification, tracing, and continuity-checking needs.
Wire Tracer Kit
Identify wire pairs, check continuity, test telephone line polarity
- Transmitter with output terminated in a modular RJ11 phone connector, plus alligator clips for unterminated wiring
- Non-contact amplifier probe audibly identifies the selected wire so you can trace from source to termination
- Adjustable sensitivity control reduces false detections in busy trunking or ceiling voids
Tone Generator and Amplifier Probe Kit
Heavy-duty kit with audible tone easily identifies wires or cables
- Insulated inductive probe tip prevents shorting conductors while tracing live-adjacent cabling
- Wire trace, continuity test, clear/busy/ringing line test, and tip/ring identification in one kit
- Alligator clips for unterminated cables plus RJ11 and RJ45 modular connectors for direct plug-in testing
Advanced Cable Locator and Tracer Kit
Safely locate, diagnose and trace hidden power, telecom and data cables
- Non-contact voltage technology with a CAT III-450V safety rating for near-live building wiring work
- Traces powered and unpowered cables inside walls, ceilings, floors, and outdoor underground runs
- Built-in worklights, coded signals, and a backlit receiver display for low-light roof spaces and ceilings
Remote and Local Continuity Tester
One-person continuity checking and wire identification, even room to room
- Bi-colour (red/green) LED remote probe lets one technician label up to three wires without a second trip
- Tests wire runs up to 3,000 metres (26-gauge minimum) — suited to long building or campus cabling
- Pulsed 20–50 mA polarity-verifying signal rules out false continuity readings on long runs
Compare the Range
← Scroll to see full table →
| Model | Best For | Method | Range / Rating | Ideal User |
|---|---|---|---|---|
| TG20 | Identifying wire pairs & telephone lines | Tone injection + non-contact probe | In-building tracing runs | Telecom & alarm installers |
| 40180 | Heavy-duty wire & cable tracing | Inductive tone probe + RJ11/RJ45 | In-building tracing runs | Electricians, data cabling techs |
| CLT600 | Locating hidden power/telecom cables | Non-contact voltage detection | CAT III-450V; up to ~50cm depth | Electricians, building inspectors |
| CT20 | Long-run continuity & wire ID | Pulsed DC continuity signal | Up to 3,000m (26-gauge min) | Electricians, CCTV/audio installers |
Applications
Electrical Certificate of Compliance (CoC) Inspections
SANS 10142-1 requires a registered person to verify circuit wiring, labelling, and continuity before issuing a CoC. Continuity testers and cable locators confirm that circuits are correctly wired and free of unintended breaks before sign-off, which matters for both new installations and pre-sale property inspections across South Africa.
Rewiring & Renovation Work
In older Cape Town and Highveld-era homes and commercial buildings, wiring is frequently unlabelled or undocumented. A wire tracer or non-contact locator lets an electrician confirm which breaker feeds which circuit, or exactly where a cable runs behind a wall, before drilling, chasing, or demolition work begins.
Telecom & Alarm Installation
Identifying the correct pair in a bundle of unmarked telephone or alarm wiring is a routine task for installers. A tone generator and probe kit lets a single technician trace and label each wire from the distribution point to its termination without needing a second person at the far end.
Facilities & Building Maintenance
Facilities teams managing large sites use continuity testers to confirm long cable runs are intact after load-shedding-related switching cycles, water ingress, or rodent damage, and use cable locators to map buried or in-wall runs before any excavation or refurbishment work.
Frequently Asked Questions
What is a cable tester used for?
A cable tester identifies, traces, or verifies the condition of an electrical, telephone, or data cable without physically following it through walls, ducting, or bundles. Depending on the tool, this can mean injecting a tone onto a wire and picking it up with a probe, checking a circuit is continuous end to end, or non-contact scanning to find a cable's physical path behind a wall. Learn more about cable testers.
What is the difference between a wire tracer and a continuity tester?
A wire tracer (TG20 or 40180) injects a signal onto a cable and uses a probe to follow that signal to find or identify it physically. A continuity tester (CT20) instead confirms a circuit is electrically unbroken end to end — the check used to label wires correctly or confirm a cable hasn't been damaged.
Can a tone generator find a break in a cable?
A tone generator and probe kit is built mainly to identify and trace a specific wire within a bundle, not to pinpoint the exact location of a break. To confirm whether a cable is broken, and roughly where, a continuity tester or a cable locator with depth detection (like the CLT600) is the more appropriate tool.
Is it safe to trace a live electrical cable?
Only with a tool rated for it. The CLT600 uses non-contact voltage technology with a CAT III-450V safety rating, letting electricians locate and verify energised cables without direct contact. The TG20, 40180, and CT20 are designed for unpowered, low-voltage telecom and data cabling only, and should never be connected to a live mains circuit.
How far can a wire tracer identify a cable?
The CT20 continuity tester can identify and label wires over runs of up to 3,000 metres (26-gauge minimum), suiting long building or campus wiring. Tone generator kits like the TG20 and 40180 are built for shorter, in-building tracing where the probe operator walks the suspected cable path.
Do I need a cable tester for an electrical Certificate of Compliance in South Africa?
SANS 10142-1 requires a registered person to verify circuit wiring, labelling, and continuity before issuing an electrical Certificate of Compliance (CoC). Continuity testers and cable locators are commonly used during this verification to confirm circuits are correctly wired, labelled, and free of unintended breaks before the CoC is signed off.
Need Help Choosing a Cable Tester?
Tell us what you're tracing, locating, or certifying and we'll recommend the right Extech tool for the job.
Or speak to Zak on 086 142 8716 or Zaid on 082 390 3989