Surge Testers & Winding Resistance Test Equipment
ED&D surge testers and winding resistance test systems support repeatable transformer testing, coil evaluation, rise-of-resistance temperature measurement, and precision low-resistance measurement in electrical safety and component test programs. The HOT-15, HOT-30, H06.10 Surge Tester, and 4176 Micro-Ohmmeter are used in test programs associated with IEC, UL, CSA, EN, and DIN requirements.
Rise-of-Resistance Temperature Testing
HOT-series systems automate winding temperature determination using the resistance method used in transformer and medical safety test workflows.
Impulse / Surge Test Capability
The H06.10 surge tester provides the controlled high-voltage pulse arrangement used in specific IEC, EN, and DIN insulation test procedures.
Precision Kelvin Measurement
The 4176 micro-ohmmeter supports low-resistance measurements from micro-ohms to kilo-ohms for coils, shunts, wire, and transformer windings.
Tell us the number of windings, resistance range, DUT type, and governing standards used in your lab so we can help match the right system.
Surge Testing and Winding Resistance Measurement for Transformer and Coil Evaluation
Surge and resistance test equipment is used to evaluate electrical insulation, transformer winding behavior, coil performance, and low-resistance electrical paths during design verification, safety testing, component evaluation, and production support.
One common approach to transformer temperature determination is the rise-of-resistance method, where winding resistance is measured before and after heating to calculate average winding temperature. This method is widely used because it reflects the average temperature of the entire winding rather than only the local point measured by a thermocouple.
Surge testing applies controlled high-voltage impulses to evaluate insulation performance and related electrical withstand characteristics. Precision low-resistance instruments are also used for transformer windings, coils, shunts, and conductors where accurate Kelvin-method measurement is required.
These products are commonly used in programs associated with IEC 60335, IEC 60601, IEC 60065, EN 60065, and DIN VDE 0860.
Important note: the equipment provides the test or measurement capability needed to carry out a given procedure. Compliance depends on the full standard, the test setup, and the governing program requirements.
Key Features Across the Surge / Resistance Product Family
- Hot winding resistance systems for rise-of-resistance temperature measurement
- Impulse / surge test capability for insulation-related procedures
- Four-wire Kelvin measurement for low-resistance accuracy
- Multi-channel transformer winding test capability on HOT-series systems
- Digital display and software-guided workflows on applicable models
- Precision micro-ohm to kilo-ohm measurement capability on the 4176
- Support for appliance, medical, electronics, and transformer test workflows
HOT-15 Hot Winding Resistance Measurement System
The HOT-15 is a hot winding resistance measurement system designed to automate transformer winding temperature determination using the rise-of-resistance method. It reduces the manual readings and calculations traditionally associated with winding temperature testing.
Product Details
- Automates winding resistance temperature measurement
- 8 measurement channels standard
- Can be connected to a second unit for 16-channel capability
- Uses the rise-of-resistance method rather than spot-temperature only measurement
- Windows-based software guides the operator through each stage
- Software creates reports and spreadsheet outputs
- Designed for transformer and winding temperature testing workflows
Associated standards: IEC 60335 and IEC 60601.
Method note: rise-of-resistance measurement is used because it estimates the average temperature of the full winding, rather than the localized spot temperature that may be obtained from a thermocouple alone.
HOT-30 Hot Winding Resistance Measurement System
The HOT-30 is a multi-channel hot winding resistance measurement system designed to automate temperature determination for multiple transformer windings. It combines resistance-channel measurement with thermocouple channel support for broader test visibility during winding heating programs.
Product Details
- Up to 8 resistance reading channels
- Four-wire measurement method
- Up to 12 temperature reading channels
- Uses Type K, 24 AWG, Teflon thermocouples
- Designed to simplify transformer winding operating-temperature measurement
- Supports multi-winding test workflows
Included accessories: 8 Cat5e data cables, 8 isolation modules, 8 banana jack sets, 8 Kelvin probe sets, 12 Type K thermocouples (72 in.), and 1 USB Type A to Type B cable.
Application note: the HOT-30 is best suited for transformer and multi-winding temperature measurement workflows where multiple resistance and temperature points must be tracked together.
H06.10 Surge Tester
The H06.10 Surge Tester is designed for impulse / surge testing procedures that apply controlled high-voltage pulses to the specimen under test. It is positioned for standards-based insulation test workflows referenced in IEC, EN, and DIN requirements.
Product Details
- High voltage supply: 10 kV DC, 1.5 mA
- Digital voltage measurement display
- High-voltage capacitor: 1 nF
- Switch arrangement according to the required figure configuration
- Interval pulser to control switching
- Two sockets in the test cabinet to connect the specimen
- BNC terminal connected in series with a voltage divider for oscilloscope connection
Referenced test clauses:
IEC 60065 / 1998-07 § 10.1 and § 14.1a Fig. 5a and Fig. 5b
EN 60065 / 1993 § 10.1 and § 14.1a Fig. 7a and Fig. 7b
DIN VDE 0860 / 1989-05 § 10.1, § 14.1a, and § 14.2.4.1 Fig. 7a and Fig. 7b
Standards note: this product is best described as apparatus for carrying out specific surge / impulse procedures, not as a general-purpose hipot tester.
4176 Programmable Digital Micro-Ohmmeter
The 4176 programmable digital micro-ohmmeter provides super-stable low-resistance measurement for hard-to-test items such as transformers, coils, shunts, and wire. It is designed for precision resistance measurement across a wide range using four-wire Kelvin connection methods.
Product Details
- Measurement range from 1 µΩ to 30 kΩ
- Basic accuracy of 0.04%
- Seven ranges, manual or auto-range
- Four-wire Kelvin binding post terminals
- Accepts banana plugs, spade lugs, or wire connections
- Intensity-adjustable and time-variable VFD display
- Remote operation through RS-232
- Optional USB interface available
Typical applications: transformer winding resistance measurement, coil testing, shunt measurement, wire resistance verification, and other low-resistance electrical checks.
Which Surge or Resistance Test Instrument Is Right for Your Lab?
| Model | Primary Use | Best Fit | Key Differentiator |
|---|---|---|---|
| HOT-15 | Hot winding resistance testing | Transformer temperature measurement workflows | 8 channels standard and expandable to 16 channels |
| HOT-30 | Multi-channel hot winding resistance testing | Multi-winding transformer programs with resistance and thermocouple monitoring | Up to 8 resistance channels and 12 temperature channels |
| H06.10 | Surge / impulse testing | Clause-specific insulation test procedures | 10 kV impulse arrangement with oscilloscope connection capability |
| 4176 | Precision low-resistance measurement | Transformers, coils, shunts, and conductors | 1 µΩ to 30 kΩ range with 0.04% basic accuracy |
Selection guidance: choose HOT-15 or HOT-30 for winding temperature determination by the rise-of-resistance method, choose H06.10 for clause-based surge / impulse procedures, and choose 4176 for precision Kelvin low-resistance measurement.
Frequently Asked Questions
What is a hot winding resistance tester used for?
A hot winding resistance tester is used to determine the average temperature of transformer windings by measuring resistance change before and after heating using the rise-of-resistance method.
Why use the rise-of-resistance method instead of only thermocouples?
The rise-of-resistance method estimates the average temperature of the entire winding, while a thermocouple typically measures temperature only at one local point.
What is the difference between the HOT-15 and HOT-30?
Both support winding resistance temperature measurement, but the HOT-30 is positioned for broader multi-winding workflows with up to 8 resistance channels and up to 12 temperature channels, while the HOT-15 emphasizes the standard hot winding resistance workflow with expansion capability.
What is the H06.10 surge tester used for?
The H06.10 is used for specific surge or impulse test procedures where a controlled high-voltage pulse arrangement is required.
What does the 4176 micro-ohmmeter measure?
The 4176 measures very low resistance values using a four-wire Kelvin method and is suitable for transformers, coils, shunts, wire, and other low-resistance electrical components.
Does this equipment itself certify compliance with IEC or UL standards?
No. The equipment provides the measurement or test capability needed to perform procedures defined by the relevant standard. Final compliance depends on the full test method and program requirements.
Tell us whether you need hot winding resistance testing, surge / impulse capability, or precision low-resistance measurement.
Typical Surge and Resistance Testing Applications
ED&D surge testers and winding resistance instruments are used in a wide range of transformer testing, coil evaluation, electrical safety workflows, and component verification.
Depending on the product and governing program, these workflows may relate to procedures associated with IEC 60335, IEC 60601, IEC 60065, EN 60065, and DIN VDE 0860.
- Transformer winding temperature determination
- Hot winding resistance testing for multi-winding products
- Motor and coil resistance-related evaluation
- Impulse / surge insulation test procedures
- Legacy electronics and audio equipment test workflows
- Bench-top engineering and safety lab use
- Low-resistance measurement of shunts and conductors
- Transformer and inductor winding resistance verification
- Production support and engineering troubleshooting
Selection note: choose the instrument based on whether your main need is winding temperature determination, clause-based surge testing, or precision low-resistance measurement.