Used / Serviceable MK Test Systems XLR-9703-01 ExLRT Loop & Joint Resistance Tester

Used / Serviceable MK Test Systems ExLRT XLR-9703-01 Loop & Joint Resistance Tester (Intrinsically Safe)

This item is a used but serviceable MK Test Systems ExLRT XLR-9703-01, offered in full working condition and tested for proper operation. It may include calibration documentation or be supplied with a current calibration certificate.

The ExLRT is a modern, lightweight, intrinsically safe loop and joint resistance tester (LRT) designed for aircraft maintenance, allowing safe use around fueled aircraft and hazardous environments. It serves as a direct replacement for legacy “yellow-box” LRT units and is approved for use by major aircraft manufacturers.

Because this is a used unit, cosmetic wear such as scuffs, light scratches, or surface blemishes may be present. Electronic and mechanical functions have been verified, and all connectors, couplers, probes, display, and internal circuitry are confirmed operational. The unit is a cost-effective option for MRO shops, airline electrical maintenance departments, or avionics service providers seeking a reliable, field-proven tool.

Technical Specifications

Safety & Environmental

• Intrinsically Safe Certification: Class 1 Div 1 (Zone 0) per ISA 60079-11 (Ex ia)

• IP Rating: IP54 (protected against dust and water spray)

• Operating Temperature: –10 °C to +40 °C (14 °F to 104 °F)

Mechanical / Physical

• Weight (main unit only): Approximately 3.0 kg / 6.6 lb

• Dimensions: 150 mm (L) × 200 mm (W) × 300 mm (H)

Electrical / Measurement

Loop Resistance Test

• Test Frequency: 200 Hz (constant current or voltage mode)

• Resistance Range: 0.5 mΩ to 4000 mΩ

• Resolution: 0.01 mΩ

• Accuracy (0.5–4 mΩ): ±(2 % of reading + 0.4 mΩ)

• Accuracy (4–40 mΩ): ±(2 % of reading + 0.4 mΩ)

• Accuracy (40–4000 mΩ): ±(5 % of reading + 0.4 mΩ)

Joint Resistance Test

• Joint Resistance Range: 0.05 mΩ to 4000 mΩ (depending on loop current)

• Resolution: 0.01 mΩ

• Accuracy: ±(5 % of reading + 0.025 mΩ + 0.25 % of loop reading)

• “Low Joint” indication: Reports “< 0.05 mΩ” when below threshold

Features / Interface

• Display: Large backlit LCD for easy readability

• User Interface: Guided test prompts with auto/manual modes

• Pass / Fail Indicators: LED and on-screen indication

• Data Logging: Internal memory for measurement storage, USB transfer

• Connectivity: USB interface; optional Bluetooth (if equipped)

• Self-Test / Calibration: Built-in self-test; on-site calibration capability (~30 minutes)

• Firmware / Software: Upgradeable for additional functions and automation

Why Choose This Used ExLRT

• Cost-effective alternative to a new unit while retaining full measurement accuracy and safety certification.

• Intrinsically safe design allows safe operation in hazardous areas, including aircraft fuel zones.

• Lightweight and ergonomic construction reduces operator fatigue.

• On-site calibration capability minimizes downtime and shipping costs.

• Data logging and automation-ready features improve documentation and workflow efficiency.

• Trusted performance—recognized and approved by major aircraft OEMs and maintenance facilities worldwide.