Metrel
MI 3250 Micro-Ohmmeter 10A

Metrel MI 3250 Micro-Ohmmeter 10A: Secure Your Electrical Integrity

Stop relying on low-current continuity checks. The MI3250 delivers lab-grade accuracy for critical low-resistance testing on busbars, switches, and windings.

Contact our sales team today or request a demonstration to learn more about how the Metrel MI 3250 Micro-Ohmmeter 10A help with your specific industrial application.

Precision Engineering for Industrial Reliability

The Metrel MI 3250 is a robust, lightweight solution designed for the most demanding applications, including electrical power systems, industrial machinery, and distribution networks. It expertly performs bidirectional resistance measurement from an exceptional 0.1 µΩ up to 2000 Ω.

Crucially, the Metrel MI 3250 features a highly efficient 10 A current source that generates the full 10 A into a 200 mΩ load for a substantial 15 minutes without any risk of overheating. This sustained performance is vital for accurate testing of highly inductive loads. The core of the instrument‘s accuracy lies in the 4-lead Kelvin method combined with an automatic bidirectional procedure, which expertly eliminates the effects of thermal electromotive force (EMF) and lead resistance errors.

Key MI3250 Features:

• Sustained 10 A Output: Guaranteed performance into 200 mΩ for 15 minutes.
• CAT IV / 300 V Safety: High overvoltage protection for substation testing.
• Noise Immunity: Integrated 50 Hz / 60 Hz ripple detection and rejection.
• Operate While Charging: Continuous workflow via mains power.
• Advanced Data: 1000 internal memory locations for Metrel MI 3250 results.

Technical Depth: Specifications and Applications

Metrel MI 3250 Key Specifications:

Versatile Applications for the MI3250:

• Electrical Power Systems: Measuring circuit breaker contacts and switchgear.
• Connections and Bonding: Testing busbar joints and earthing connections.
• Rotating Machinery: Accurate winding measurement on motors and generators.
• Industrial Systems: Checking fuses, cable joints, and critical safety bonds.
• Static Machinery: Low resistance testing on small to medium-sized transformers.
• Specialised Testing: Rail and pipe bonds, and lightning conductor bonding.

What comes with the Metrel MI 3250?

• MI 3250 Micro-Ohmmeter 10A Instrument
• 2.5 m Test cables with Kelvin Clip
• 2 m Test cables (2 x black, 2 x red)
• 4 x Crocodile clips, 2 x Test probes (red, black)
• PC SW HVLink PRO (for downloading MI3250 results)
• 6 x NiMH batteries, Mains, USB, RS232 cables, Accessories bag

❓ Frequently Asked Questions (FAQ)

Q1. Why is the 10 A test current from the Metrel MI 3250 Micro-Ohmmeter important?

A. The high 10 A current provided by the Metrel MI 3250 is crucial because it helps to break down surface contamination, rust, and oxide layers on the components being tested (e.g., switch contacts, busbar joints). A higher current also yields a stronger voltage signal, dramatically improving the signal-to-noise ratio and providing a more stable, repeatable, and accurate resistance reading, especially on the sub-milli-Ohm range.

Q2. Can the MI3250 compensate for temperature?

A. Yes, the MI3250 features temperature compensation. Using an optional temperature probe, the instrument can automatically measure the ambient temperature and adjust the resistance reading to a standardised reference temperature, which is essential for comparing measurements taken at different times or locations.

Q3. How does the Metrel MI 3250 improve efficiency in the field?

A. The Metrel MI 3250 is designed for field efficiency. Its lightweight, portable design and high-capacity internal batteries (>1000 measurements at 10 A) are key. Furthermore, the ability to operate the MI 3250 while simultaneously charging the batteries via the mains connection ensures maximum productivity and continuous workflow.