The UT117C is a common field meter. A careful teardown shows the input protection stack, ADC front-end, and rotary switch—the usual wear points when readings go weird.
If readings drift
- Inspect banana jack welds and rotary contacts for oxidation.
- Check PTC/fuse protection after an overload event.
- Calibrate only if you have a known reference; do not invent pots to twist.
Safety notes
Meters that survived a mains misconnect may look fine and still lie—verify against a second meter before trusting safety-critical measurements.
FAQ
CAT rating?
Respect the marked CAT/voltage; the plastic shell is not optional armor.
Worth opening?
Mostly for education or fuse replacement.
Photo: Unsplash. Repair steps are general guidance—model variants differ. Unplug power and follow ESD-safe practice before opening devices.