Insulation Resistance Tester (Megohmmeter)
Calibrate megohmmeters for verifying electrical insulation integrity to safety standards.
Standards
IEC 60664-1, IEC 61557-2, ISO/IEC 17025
Typical Interval
12 months
Uncertainty Range
±5% of reading
What Is Insulation Resistance Tester (Megohmmeter)?
Megohmmeters apply high voltage (500V–5000V) and measure leakage current to test the insulation integrity of cables, motors, transformers, and other electrical equipment. Calibration verifies both the applied test voltage and the resistance indication.
IEC-compliant electrical maintenance programs require insulation test results from calibrated instruments to confirm safe insulation condition.
Applicable Standards
Primary standards: IEC 60664-1, IEC 61557-2, ISO/IEC 17025
ISO/IEC 17025-accredited laboratories must maintain an unbroken traceability chain from the calibration result back to NIMT (Thailand's national metrology institute) or another internationally recognised NMI.
Typical Measurement Uncertainty
Expanded uncertainty is typically ±5% of reading, depending on the measurement range, reference equipment used, and environmental conditions. The actual uncertainty will be stated on your calibration certificate.
Recommended Calibration Interval
A calibration interval of 12 months is generally recommended. The appropriate interval for your specific instrument depends on usage frequency, environmental exposure, and any applicable regulatory or customer requirements.
What Your Calibration Certificate Will Include
- Calibration results — instrument indication vs. reference value at each test point
- Error and expanded uncertainty (U) at k=2 (95% confidence level)
- Traceability chain to NIMT or a recognised NMI
- Environmental conditions during calibration (temperature, humidity)
- Calibration date, certificate number, and authorised signature
Find a Insulation Resistance Tester (Megohmmeter) Calibration Lab in Thailand
ThaiLabHub lists ISO 17025-accredited calibration laboratories across Thailand. Search our directory to find labs that offer insulation resistance tester (megohmmeter) services, with scope details, location, and contact information.
For Labs: Manage Insulation Resistance Tester (Megohmmeter) Jobs with LabSync
LabSync helps Thai calibration laboratories manage jobs, issue traceable certificates, calculate GUM uncertainty budgets, and generate Thai tax reports (PP30 + WHT) — all in one system.
Frequently Asked Questions
Why is it important to calibrate a Insulation Resistance Tester (Megohmmeter)?+
Uncalibrated Insulation Resistance Tester (Megohmmeter)s can have drift errors that cause false readings, leading to incorrect safety assessments or product failures. Regular calibration ensures measurements remain traceable to national/international standards and meet regulatory requirements such as IEC 60664-1, IEC 61557-2, ISO/IEC 17025.
How often should a Insulation Resistance Tester (Megohmmeter) be calibrated?+
Most Insulation Resistance Tester (Megohmmeter)s should be calibrated every 12 months under normal operating conditions. High-use environments, harsh conditions (vibration, temperature extremes), or regulatory requirements (FDA, GMP, ISO 17025) may necessitate more frequent calibration. Always follow the manufacturer's recommended interval as a baseline and consult your lab's quality plan.
What does a Insulation Resistance Tester (Megohmmeter) calibration certificate show?+
A calibration certificate issued under ISO/IEC 17025 includes: the instrument identification (make, model, serial number), the reference standards used (with their own traceability chain), the measurement points tested, before/after correction values, the expanded measurement uncertainty (±5% of reading), the environmental conditions during calibration, the calibration date and next-due date, and the signature of the authorized calibration engineer. This certificate is the evidence required for audits and accreditation.
Labs offering electrical calibration
Nakhon Ratchasima Metrology Center
Nakhon Ratchasima
ISO/IEC 17025:2017Phuket Marine Calibration Center
Phuket
ISO/IEC 17025:2017Eastern Seaboard Calibration Center Chonburi
Chonburi
ISO/IEC 17025:2017National Institute of Metrology Thailand (NIMT)
Pathum Thani
ISO/IEC 17025:2017 (TIS 17025-2561)Central Calibration Laboratory Bangkok
Bangkok
ISO/IEC 17025:2017Nonthaburi Precision Laboratory
Nonthaburi
ISO/IEC 17025:2017Related Calibration Services
Manage calibration with LabSync
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