Status: Current and older Megger transformer testers alike: the TTR, MTO, FRAX and IDAX lines, the Delta power-factor sets, and earlier models that crews still rely on. Every one of them can be repaired and calibrated here.
Whether a power transformer stays in service often comes down to a handful of readings: turns ratio, winding resistance, power factor and the shape of a frequency response sweep. When a Megger TTR, MTO, Delta, FRAX or IDAX drifts or fails, those readings stop being trustworthy. We repair the full transformer test line and recalibrate each set so the numbers you put in a test report hold up.
Common Megger Transformer Tester Problems We Fix
- Ratio, resistance or power factor readings that have crept out of tolerance as the measurement circuits age
- MTO that cannot reach its rated test current for winding resistance
- No connection to the PC over USB, RS-232 or Ethernet
- Blank or unresponsive display or touchscreen
- Errors across every range, pointing to drift in the internal reference
- Portable set whose battery no longer lasts a test day
- Test lead connectors that cut in and out
Seeing a fault that isn’t covered here? Email us the model and the error or reading you get, and we will point you in the right direction.
Megger Transformer Test Equipment Models We Repair
| Model | Description | Service |
|---|---|---|
| Megger TTR330 | Transformer turns ratio tester, 3-phase | Request Repair |
| Megger TTR310 | Transformer turns ratio tester | Request Repair |
| Megger TTR300 | Transformer turns ratio tester | Request Repair |
| Megger MTO330 | Transformer ohmmeter, 50 A | Request Repair |
| Megger MTO300 | Transformer ohmmeter | Request Repair |
| Megger MTO210 | Transformer ohmmeter | Request Repair |
| Megger FRAX | Frequency response analyzer for transformer windings | Request Repair |
| Megger IDAX350 | Insulation diagnostic analyzer | Request Repair |
| Megger IDAX300 | Insulation diagnostic analyzer | Request Repair |
| Megger Delta 4310 | Power factor test set | Request Repair |
| Megger Delta 4110 | Power factor test set | Request Repair |
| Megger CDAX 605 | Power factor tester | Request Repair |
| Megger CB-100 | Power factor tester | Request Repair |
| Megger 670070 | Dissipation factor test set | Request Repair |
| Megger 670065 | Dissipation factor test set | Request Repair |
| Megger 670025 | Factor test set | Request Repair |
| Megger CTER-91 | Current transformer tester | Request Repair |
| Megger MCTT-10 | Transformer tester | Request Repair |
| Megger MLR10 | Leakage reactance tester | Request Repair |
| Megger MRCT | Transformer tester | Request Repair |
What Calibration Covers on Megger Transformer Test Sets
Each instrument family measures something different, so calibration follows the instrument:
- TTR turns ratio sets: ratio accuracy and phase deviation across the ratio range
- MTO transformer ohmmeters: DC test current and winding resistance readings
- Delta, CDAX and dissipation factor sets: capacitance and power or dissipation factor readings
- FRAX and IDAX analyzers: a verified sweep, so frequency response and dielectric results report correctly
Each set ships with a NIST-traceable certificate, which also serves as the annual calibration verification Megger recommends.
Sending In a Megger Transformer Tester
- Reach out first. Email us or complete a service request listing the model and what it is doing.
- Ship the instrument. Wherever you are in the US, you can send it to us, and we will provide a prepaid label on request.
- Approve before we start. You get a firm, no-obligation quote once diagnosis is complete, and no repair happens until you approve it.
Email: info@junecompany.com | Transformer test sets repaired here are covered for 90 days on parts and labor and return with NIST-traceable calibration.
Frequently Asked Questions
How much does Megger transformer test equipment repair cost?
Cost depends on the instrument and the fault. A flat evaluation fee starts the process and is credited to the repair, and you approve a firm price before any parts are replaced.
How long does the repair take?
Most TTR, MTO and Delta repairs ship back within 1 to 5 business days of arrival, and expedited service can be arranged. FRAX and IDAX diagnostic units may take longer, which the quote will tell you.
My TTR ratio readings no longer match the nameplate. Can you recalibrate it?
Yes. Measurement-circuit and reference drift on the TTR turns-ratio sets is repairable and recalibrated against our standards, then returned with a NIST-traceable certificate so your ratio and phase-deviation results are trustworthy again.
My MTO won’t reach its rated test current for winding resistance. Is that repairable?
Yes. High-current source degradation on the MTO transformer ohmmeters is a common fault, and it’s repairable so the set delivers full DC test current and stable winding-resistance readings.
My FRAX or IDAX won’t complete a sweep. Can you fix it?
Yes. We service the SFRA frequency-response circuitry on the FRAX and the dielectric-frequency-response hardware on the IDAX, restored and verified so diagnostic sweeps run and report correctly.
Megger recommends annual calibration. Do you provide a certificate?
Yes. Recalibration against our reference standards is part of every repair, and the NIST-traceable certificate that comes with it covers the yearly check Megger recommends for these sets.
My transformer tester isn’t in the table. Do you service it?
Most likely, yes. Alongside the TTR, MTO, FRAX, IDAX, Delta and CDAX sets we also work on the CTER, MCTT, MLR and MRCT testers; choose the nearest model or email us. Since a full transformer workup usually includes winding insulation tests, we offer Megger insulation tester repair as well.
Who uses Megger transformer test equipment?
Electric utilities, transformer-maintenance contractors, substation engineers, power-generation facilities, and industrial high-voltage maintenance teams rely on the TTR, MTO, FRAX, IDAX, and Delta instruments to assess turns ratio, winding resistance, winding deformation, and insulation condition. For full manufacturer details, see Megger’s TTR transformer turns ratio testers page.
Megger substation and maintenance testers
Transformer workups with a TTR or MTO usually involve these other Megger maintenance testers:
