Insulation Testers


Zedflo – Insulation Testers

Insulation testing is critical to ensuring electrical safety and performance in various industries, ranging from residential to high-voltage industrial applications. Insulation testers are essential for evaluating electrical insulation’s integrity and safety.

We offer everything from the advanced features of 10 kV insulation testers designed for high-voltage environments. Additionally, we offer products with the convenience of wireless recording capabilities and the simplicity of basic 1 kV testers suitable for standard low-voltage electrical systems.

As a company, we can consult on different types of insulation resistance testers and evaluate their accuracy. Furthermore, we can discuss best practices in insulation testing to ensure optimal safety and performance. Whether you’re a seasoned electrician or a novice in the field, our products will give you a selection of insulation testing equipment to choose from.


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    MI 3210 TERAOHM XA 10KV

    Portable (battery or mains powered)

    Excellent IP protection (IP65)

    High DC test voltages of up to 10 kV

    CAT IV protection

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    MI 3200 TERAOHM 10 KV

    Portable (battery or mains powered)

    High DC test voltages up to 10kV

    PI, DD and DAR calculation

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    Portable (battery or mains powered)

    Excellent IP protection (IP65 case closed and IP54 case open)

    High test voltages up to 5 kV

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    Portable (battery or mains powered)

    High DC test voltages up to 5 kV

    Insulation resistance measurements up to 10 TΩ

    Large LCD screen

    Data can be downloaded to PC

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    MI 3202 GIGAOHM 5 KV

    Five test voltages up to 5 kV

    1 TΩ resistance measuring range

    Large analogue/digital LCD screen

    Strong and durable carrying case

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    MI 2077 TERA OHM 5 KV

    Insulation resistance measurements up to 5TΩ

    PI, DD and DAR testing

    Data can be downloaded to PC

    Lightweight design

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    Test voltages up to 2.5 kV

    Measuring range up to 100 GΩ

    PI and DAR indexes

    Built-in charger

The Purpose of Insulation Testing

Insulation testing is crucial for maintaining electrical safety and performance. It helps identify aged, damaged, or substandard insulation, leading to electrical faults, equipment failures, and hazardous working conditions.

Utilise our equipment to test everything from electrical motors to electrical devices and up to high-voltage equipment. Get reliable results and identify problems with your equipment to ensure safety and efficiency with us.

What is an Insulation Tester?

An insulation tester, is a device used to measure the insulation resistance of electrical wiring and components. This testing ensures that insulation adequately prevents electrical accidents like shocks or fires. We have a wide range in stock and can provide consultation regarding usage and training. Contact us today to get more information.

How Do Insulation Testers Work?

Insulation testers apply a high-voltage signal (typically between 1 kV and 10 kV) to the tested component. The device then measures the current flowing through the object and subsequently a resistance measurement according to Ohm’s law V=IR. Higher resistance values generally indicate good insulation, while lower values suggest deterioration or faults.

How to Choose the Right Insulation Resistance Tester

Choosing the right insulation resistance tester involves considering the voltage level of systems that will be tested. Specialist equipment allows the user to correctly test if the levels of resistance are fit for purpose at high accuracies. Features required like data logging or wireless capabilities are available on certain models. In addition, we must consider the ease of use, durability, and manufacturer support of the products we recommend. Get in contact with us to help you choose the best insulation resistance testing equipment for your situation or application.

The Difference In Types of Insulation Testers

Insulation resistance testers range from basic manual models to advanced digital testers with features like memory storage, trend analysis, and wireless capabilities. They also vary in voltage ranges, from 1 kV for basic applications to 10 kV or higher for industrial use. We believe in providing a wide range of products to meet the plethora of needs our clients have.

Basic 1 kV Testing: Simplified Options

Our 1 kV insulation testers are highly sufficient for standard electrical systems and residential applications. While they are user-friendly our products are also cost-effective. In addition to ease of use and low cost, they provide testing capabilities, such as continuity checks and spot readings of insulation resistance. Our 1 kV testers suit electricians and maintenance technicians who need reliable, straightforward equipment. Our multifunction installation testers also include 1 kV insulation testing functions. Contact our friendly staff today to see if you need our 1 kV testing kits or if you need a more advanced solution.

Complete 5 & 10 kV Solution: Advanced Features

Our 5 kV & 10 kV insulation testers are designed for high-voltage applications, offering advanced diagnostic features like step voltage testing, dielectric absorption ratio (DAR), and polarisation index (PI). Electricians can utilise our products for testing high-capacity motors, transformers, and cables. Our comprehensive range of testers often includes the latest features, such as digital displays, data logging, easy data analysis.

Insulation Tester vs. Megger

While “Megger” is a brand name, it’s often used interchangeably with “insulation resistance tester.” However, not all testers are Meggers (by brand). Our Metrel brand of testers is known for manufacturing high-quality testers, with many feature options and different price points for all your insulation testing needs.

Understanding the R-Value in Insulation Testing

The R-value in insulation testing refers to the resistance measurement. Higher R-values indicate better insulation quality. Understanding the expected R-values for different types of equipment and environments is crucial in assessing insulation health accurately. If you are unsure of what you are looking at or require consultation contact us.

What Constitutes a Good Reading in Insulation Testing?

Good readings in insulation testing vary depending on the equipment and standards. Generally, readings above 1 megaohm are considered acceptable, but much higher values are standard for more sensitive or high-capacity equipment. Refer to your applicable standard for specific information.

Evaluating the Accuracy of Testers

The accuracy of an insulation tester is essential for reliable diagnostics. Accuracy can be influenced by the tester’s design, calibration, and environmental factors. Regular calibration and understanding the device’s limitations are important for accurate measurements.

Best Practices in Insulation Testing

Best practices in insulation testing include following safety protocols, applying the correct test methods, regular calibration of equipment, and thorough analysis of test data. This ensures not only the tests’ accuracy but also the technicians’ safety.

Get in Touch With Us Today

Our range of testers will satisfy anyone in the electrical field, offering safety and performance. From the advanced 5 & 10 kV models perfect for industrial applications to the user-friendly 1 kV testers for domestic systems, we have the ideal tool for every job.

Our products ensure reliable, accurate testing with features like wireless recording and advanced diagnostics, simplifying your work while enhancing safety.

Let us help you with your insulation testing needs and experience the difference in quality and efficiency.