
Ring/Donut, or encircling probes are made to fit various fastener head diameters. They are mainly used for subsurface crack detection with the fastener in place. They are available in both bridge and reflection configurations.
Advantages
- Ideal for subsurface defects.
- Inspection can be done with the fastener still in place.
- Various sizes available.
- Available with Powerlink™ technology.
- Available with bridge or reflection configuration.
Absolute Bridge
Absolute bridge type probes
- Internal reference coils ensure the best match to the test coil when using a Triax (Fischer™*) or Powerlink™ connector.
- Shielded coil for higher resolution.
- Detects cracks in all directions.
- Probe-type commonly used worldwide.
- Cost effective option.
Olympus absolute bridge type probes give a clean and strong signal as shown.
* All brands are trademarks or registered trademarks of their respective owners and third-party entities.

Coil
Frequency
ID mm (in.)
OD mm (in.)
Connector
Part ID
U8 #
Cable
Item #
Bridge
50 Hz to 500 Hz
8.89 (0.35)
19.05 (0.75)
Triax Fischer
LR017-5-TF
U8636097
9122244
U8800091
Bridge
50 Hz to 500 Hz
17.8 (0.7)
33 (1.3)
Microdot
LR0113-5
U8636094
9102894
U8800041
Bridge
50 Hz to 500 Hz
19.05 (0.75)
32.5 (1.28)
Microdot
LR0114-5
U8636071
9102894
U8800041
Bridge
50 Hz to 500 Hz
19.05 (0.75)
32.5 (1.28)
Triax Fischer
LR0114-5-TF
U8636072
9122244
U8800091
Bridge
500 Hz to 10 kHz
6.48 (0.255)
16.51 (0.65)
Microdot
LR106-1
U8636107
9102894
U8800041
Bridge
500 Hz to 10 kHz
6.48 (0.255)
16.51 (0.65)
Triax Fischer
LR106-1-TF
U8620455
9122244
U8800091
Bridge
500 Hz to 10 kHz
7.62 (0.3)
19.05 (0.75)
Triax Fischer
LR107-1-TF
U8636077
9122244
U8800091
Bridge
3 kHz to 20 kHz
7.99 (0.315)
17.2 (0.68)
Triax Fischer
LR506-2
U8620265
9122244
U8800091
Bridge
50 Hz to 500 Hz
25.4 (1.0)
38.35 (1.51)
Microdot
LR0115-1
U8636095
9102894
U8800041
Bridge
300 Hz to 5 kHz
12.7 (0.5)
25.4 (1.0)
Triax Fischer
LR0510-5-TF
U8636098
9122244
U8800091
Bridge
300 Hz to 5 kHz
7.62 (0.3)
19.81 (0.78)
Triax Fischer
LR058-1-TF
U8636089
9122244
U8800091
Reflection Absolute
Reflection type probes
Also known as send-receive or driver-pickup probes
- Provides a similar response to the absolute bridge probe.
- Available with stacked or concentric driver and pickup coils.
- Enables crack detection in all directions.
- Withstands variations in temperature.
- Operates over a wide frequency range.
Olympus reflection absolute type probes give a clean and strong signal as shown.

Resources
기술자료
기술자료
/ko/learn/white-papers/eddy-current-probes-and-application-guide
제품 리소스
브로셔
https://evidentscientific.com/ko/downloads/brochures?product=Ring%2FDonut+Probes