Testing Equipment You Probably Don't Have, But You Definitely Need in Your Electrician Tool Belt!

Luke Begley

Key Takeaways

  • Miniature voltage testers offer a simplified, portable solution for quick voltage checks.
  • Specialized equipment like the Klein ET310 facilitates precise circuit identification.
  • Advanced testing tools such as thermal imagers and clamp-on ammeters add depth to electrical diagnostics.

The Importance of Proper Test Equipment

When considering the array of testing devices at your disposal, the value of each tool in efficiently diagnosing and resolving electrical issues is evident. For clear-cut voltage testing, a miniature voltage tester is a must-have in your toolkit. This compact device provides straightforward voltage readings without the complications of additional modes, making it a reliable choice over a tick tracer, which can sometimes provide misleading results.

In complex scenarios where you're faced with the task of identifying circuit breakers, the Klein ET310 proves indispensable. This innovative tool combines a transmitter and receiver to simplify the process of pinpointing circuits, minimizing time spent on trial and error.

Venturing into thermal management, a thermal imager becomes an essential piece of test equipment. Unlike a standard thermometer, a thermal imager translates heat signatures into visual data on a screen, allowing you to detect overheating components with precision, an invaluable asset for preventive maintenance.

For varied testing requirements, a digital multimeter (DMM) stands as a versatile tool equipped with numerous functions. Offering more than simple voltage detection, a DMM delivers comprehensive diagnostic capabilities.

On the other hand, an amp clamp or clamp-on ammeter enriches your capacity to measure current flow without direct contact, offering non-invasive current readings that are both safe and convenient.

When visibility is a challenge, such as within conduits or behind walls, a borescope becomes critical. The integration of a camera and light facilitates inspection in otherwise inaccessible areas, with the added benefit of interfacing with your smartphone for real-time viewing and recording.

For the investigation of insulation integrity, especially for electricians who work with underground conduits or transformers, the megohmeter, commonly referred to as a mega, becomes a critical tool. It allows you to ensure that no electrical leakage or damage has compromised your work during installation.

Finally, assessing earth resistance with a three-point fall-of-potential meter can prove essential in meeting regulatory compliance and achieving safe grounding practices. The device offers a direct approach to evaluating the resistance of earth, which is crucial in grounding electrical systems effectively.

In summary, your test equipment collection should be as wide-ranging as the challenges you face in the field. Each testing device is designed for specific scenarios, enhancing your ability to deliver quality workmanship safely and efficiently.

Miniature Voltage Tester

When you need to quickly check for voltage without carrying a full toolkit, the miniature voltage tester is an exceptional carry-along tool. Unlike more complex devices, it doesn't include resistance or amperage settings; it's exclusively designed to test voltage. Here's why it's a reliable choice over a typical non-contact voltage tester, or "tick tracer," which might mislead you under certain circumstances:

  • Safety: Offers more reliable readings to prevent potential misjudgment and hazards.
  • Portability: Small enough to fit in your pocket, making it highly convenient.

For example, the Klein ET310 is a pocket-sized device that simplifies voltage testing. It provides accurate voltage detection, ensuring that you can walk into any site and smoothly perform your checks without the burden of additional tools.

Usage Simplicity:

  • No complex settings, simply a voltage tester.
  • Single-function focus means it's easy-to-use.


  • Immediate Readiness: Always ready for a quick voltage test.
  • Reduced Equipment: No need for a full set of tools for simple tasks.

Applications: Ideal when doing a walkthrough or a quick inspection, allowing for swift voltage assessments without hassle.

Remember, the utility of the tester lies in its straightforward functionality – aimed at making your job faster and keeping you safer with precise voltage readings.

Klein ET310 Transmitter and Receiver

When you're caught up in the field having trouble identifying circuits, you'll find the Klein ET310 indispensable. Imagine plugging in a device that resembles a standard plug tester and wielding a wand to effortlessly trace circuits back to the panel. It simplifies your task remarkably.

Here's what makes the ET310 stand out:

  • Ease of Use: Plug in the transmitter into the circuit, and use the receiver to detect the signal.

  • Safety Enhancement: Reduces risk by clearly identifying circuits without guesswork.

  • Convenience: Eliminates the need for multiple tools; this combo does the trick.

  • Portability: The handy size of both the transmitter and receiver means they won't weigh you down.

  • Efficiency: Saves you considerable time when tracing circuits as compared to traditional methods.

Remember, while it operates by sending signals through the wiring, the detection process with the receiver feels almost wireless. It's an essential tool for safe and effective electrical troubleshooting.

Thermal Imager Use in Electrical Testing

Thermal Imagers offer a significant advantage in electrical testing by allowing you to visualize heat signatures on a screen. This is especially useful in identifying overheated components which could indicate electrical issues. A thermal imager operates somewhat like a thermometer, but with enhanced capabilities:

  • Visual Temperature Reading: Unlike a standard temperature gun, a thermal imager displays temperature in a visual format, making it easier to pinpoint hot spots accurately.
  • Identifying Problem Areas: If you suspect an issue with a breaker, switch, or outlet, a thermal imager can reveal the exact location of excessive heat.
  • Enhanced Safety: By detecting potential hazards before physically touching the electrical component, this tool improves safety during inspections.

In practice, using a thermal imager is straightforward:

  1. Power on the thermal imager.
  2. Aim the device at the electrical component you wish to test.
  3. Inspect the screen for color variations that indicate temperature differences.
  4. Identify areas of concern marked by unusually high-temperature readings.

Employing a thermal imager in electrical testing not only aids in early detection of potential electrical failures but also contributes to maintaining system integrity and ensuring workplace safety.

Understanding Digital Multimeters

Digital multimeters, or DMMs, are versatile tools with a variety of settings and functions for measuring electrical values. When you see a device with numerous dials and knobs, you're likely looking at a DMM. This contrasts with simpler testers, which may include a voltage testing function but don't offer the same range of measurements.

Key features of a DMM include the ability to measure:

  • Voltage
  • Resistance
  • Amperage
  • Continuity

Some DMMs come with an amp clamp, which allows for current measurement without direct contact to the conductor. This feature is particularly useful for measuring current on a conductor by simply clamping around it.

Additional capabilities often include advanced functionality like:

  • Checking temperature with a thermal imager function, allowing you to see heat signatures on a screen and detect hot spots on breakers or wiring.
  • Utilizing a borescope, a tool with a camera on the end, for visual inspection within walls or conduits, complete with lighting and the ability to Bluetooth the output to your device.

Moreover, specialized equipment like megohmmeters can send high voltage signals through conductors to test for insulation breakdowns or leakage, an essential function after wiring pulls or when examining transformer windings.

In advanced testing scenarios, you might use an earth resistance tester such as a three-point fall of potential meter. This tool is designed to measure the resistance of the earth and is often used to ensure your grounding system meets the required resistance standards, which is typically no more than 25 ohms.

For identifying circuits, tools like the transmitter and receiver combo can simplify your work. By plugging in the transmitter and using the receiver at an electrical panel, you can determine which breaker corresponds to which circuit without tracing wires manually.

In your varied work as an electrician, these sophisticated devices should be a part of your toolkit, assisting you in diverse environments and with various materials, enhancing your ability to diagnose and resolve electrical issues with precision and safety.

Clamp-On Ammeter Explained

A clamp-on ammeter, often referred to as an amp clamp, is an essential tool for electricians like you. Its primary function is to measure the current flowing through a conductor without the need for physical contact.

Design and Functionality:
The ammeter has a hinged jaw integrated into the meter, enabling you to open it and clamp it around an electrical wire. This design allows you to safely measure AC current.


  • No need to cut off the circuit to take measurements, as with traditional meters.
  • Measures the magnetic field around the conductor to determine current.
  • Safe, efficient, and non-invasive method suitable for various applications.

Features to Look For:
Some features to consider when using or selecting a clamp-on ammeter:

  • Jaw Size: Suitable for the wire diameter. Larger jaws are available for bigger conductors.
  • Current Range: Assure it matches the required range for your electrical tasks.
  • Accuracy: Check the specification to ensure precision in readings.

Advantages Over Standard Testers:

  • Quick and real-time current readings.
  • Enhanced safety due to the non-contact measurement process.
  • Can perform measurements in tight spaces where traditional probes might not reach.

When to Use:
You should consider using a clamp-on ammeter for tasks like checking load currents, detecting circuit overloads, or verifying the operation of electrical equipment. In essence, it is a versatile tool that significantly simplifies electrical diagnosis and troubleshooting.

Applications of Borescopes in Electrical Work

As an electrician, you'll find that a borescope is an indispensable tool for inspecting areas that are typically out of sight. Borescopes are equipped with a camera at the end allowing you to navigate through confined spaces effortlessly.

Key Uses:

  • In-wall Inspections: When running wires, encountering blocks within the wall is common. A borescope lets you examine these areas without invasive techniques, saving both time and labor costs.
  • Conduit Examination: Sometimes, you need to verify the condition inside a conduit or detect clogs. This tool proves to be efficient for such applications.


  • Enhanced Visibility: The integrated light of the borescope is quite beneficial when working in poorly lit environments.
  • Real-time Analysis: By connecting the borescope to your smartphone via Bluetooth, you can view live feeds, record videos, or take snapshots.



Camera lens

Provides visual access to hidden areas.

Light function

Aids in visibility in dark spaces.


Enables easy connection to mobile devices.

Klein app

Facilitates documentation and sharing of findings.

Incorporating a borescope into your toolkit enhances your diagnostic capabilities when dealing with the unseen. Whether it’s snaking through a wall to locate a drill hole or identifying obstructions in conduits, your ability to swiftly diagnose and resolve issues is greatly improved.

Insulation Testing with a Megohmmeter

When carrying out insulation testing, a megohmmeter, commonly referred to as a megger, proves to be an essential tool. This specialized device is designed for evaluating the condition of electrical insulation by detecting leakage currents and any damage that might have compromised the insulation's integrity.

Testing Process:

  • The megohmmeter sends a high voltage signal through a conductor.
  • It measures resistance and detects any current that escapes due to damaged insulation.


  • You can use it to check the insulation of wires after pulling through conduits.
  • It's particularly useful for testing underground conductor installations.
  • It helps in assessing transformer windings, revealing if insulating materials remain intact.

Key Advantages:

  • Ensures the safety and functionality of electrical systems by verifying insulation health.
  • The test results can indicate the need for maintenance or replacement of electrical components before they fail.

Should you find the insulation compromised, taking corrective measures promptly can prevent potential hazards and maintain system efficiency.

Remember, these devices not only measure basic resistance like a typical multimeter but also subject the insulation to high voltages to ensure reliability under stress. It's a precautionary step that can save both time and resources in the long run by mitigating electrical risks.

Earth Resistance Testing

When you're dealing with grounding systems, your goal is to ensure a low-resistance path to earth to protect people and equipment during electrical faults. To achieve this, you might be familiar with striving for a standard of 25 ohms or less to ground, which can be quite challenging depending on geographic and soil conditions. The tool that you should consider indispensable for this is an earth resistance tester, specifically a three-point fall-of-potential meter.

The three-point fall-of-potential meter is a diagnostic tool that measures the resistivity of the earth. This equipment allows you to test the effectiveness of a ground system by measuring how the current flows through the soil and evaluating the earth's resistance to that current. Various factors like soil composition, moisture content, and temperature affect these measurements. Here's what you need to know about utilizing this device:

Using the Three-Point Fall-Of-Potential Meter

  • Placement:
    • Position two earth spikes into the ground at a set distance from each other and from the earthing system.
  • Connection:
    • Connect the meter to the earthing rod and the spikes, forming a triangle or 'fall-of-potential.'
  • Measurement:
    • Activate the meter to send a current through the circuit you've created. It records the flow of current and calculates the resistance of the earth.
  • Interpretation:
    • Readings will inform you of the ground resistance, with lower values indicating better earthing.

Factors Impacting Earth Resistance:

  • Soil Type:
    • Sand, clay, rock, and their moisture level play a crucial role.
  • Temperature and Weather:
    • Soil resistivity changes with temperature and weather conditions.
  • Soil Composition:
    • The presence of minerals, rocks, and other elements can alter resistance values.

Remember, in grounding, resistance is your adversary. Having a three-point fall-of-potential meter empowers you to ensure that your grounding systems are up to the task, thereby maintaining safety standards and protecting your electrical infrastructure.

Conclusion on Uncommon Electrical Testers

Your toolkit may already be extensive, but incorporating lesser-known testers can significantly enhance your troubleshooting capabilities. First off, consider the convenience of having a miniature voltage tester—a compact tool without the bells and whistles of a multimeter, yet perfect for quick voltage checks. Avoiding the pitfalls of non-contact voltage testers like tick tracers, this small device delivers reliable voltage readings and fits effortlessly in your pocket.

The Klein ET310 digital circuit breaker finder exemplifies innovation with its transmitter/receiver duo. This tester simplifies the task of identifying circuits, by transmitting a signal to a receiver that you navigate around the panel with, determining which breaker corresponds to which circuit without trial and error.

As you move to more technologically advanced tools, the thermal imager emerges as a game changer. Unlike a standard thermometer, this device visually represents heat signatures on a screen, allowing you to locate potential hotspots on breakers, switches, and connectors with precision.

Moreover, the digital multimeter (DMM) you're accustomed to is just the beginning. Testers with clamp-on features expand your current-measuring capabilities, especially helpful when dealing with high-capacity conductors. Larger clamps are available to accommodate your needs when standard clamps aren't sufficient for the conductor sizes you work with.

When visibility in confined spaces becomes a concern, borescopes lend you their eyes. The camera-tipped tool, capable of illuminating dark environments, pairs with your smartphone for real-time image transmission, making the unseen seen.

Lastly, the megohmmeter, commonly referred to as a megger (not to be confused with the original brand), is essential for confirming the integrity of insulation, especially after laying underground conductors. Routine megger testing after installation will alert you to any damage incurred during the process.

And don't overlook the earth resistance tester, notably the three-point fall of potential meter. It evaluates the earth's resistance—a critical factor in grounding electrical systems, aiming for the elusive target of 25 ohms or less, which varies with soil conditions.

By broadening your array of testers, you empower yourself to diagnose and resolve electrical issues with greater efficiency and safety. Each specialized tool equips you with the means to deliver professional excellence in an increasingly complex electrical landscape.