Actuation Distances for MS-228 Cylindrical Sensor
Operate and release distances for the MS-228 M8 Threaded Magnet Sensor in the three standard AT bands when actuated (as shown in the sketches) with NdFeB standard magnets is shown below. All distances given are in mm with tolerances of ±0.5mm. Although some of the AT band / magnet combinations will produce similar actuating distances, selecting the right AT band and magnet for an application is important and can be done by going through our AT band FAQ and magnet selection guide.
Tip to tip Actuation distances

Operate Band 20-25 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | N/A | N/A |
NDR-M | 8.0 x 3.0 x 3.0 | 3.0 – 5.0 | 7.0 – 8.0 |
NDR-I | 12.0 x 3.5 x 3.5 | 6.0 – 8.0 | 11.0 – 12.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 9.0 – 12.0 | 15.0 – 16.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | 1.0 – 2.0 | 4.0 – 5.0 |
NDC-M | Ø4.0 x 10.0 | 5.0 – 7.0 | 10.0 – 11.0 |
NDC-I | Ø6.0 x 12.0 | 13.0 – 15.0 | 19.0 – 20.0 |
NDC-L | Ø8.0 x 15.0 | 21.0 – 24.0 | 29.0 – 30.0 |
Operate Band 25-30 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | N/A | N/A |
NDR-M | 8.0 x 3.0 x 3.0 | 1.5 – 3.0 | 6.0 – 7.0 |
NDR-I | 12.0 x 3.5 x 3.5 | 4.5 – 6.0 | 10.0 – 11.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 8.0 – 9.0 | 14.0 – 15.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | N/A | N/A |
NDC-M | Ø4.0 x 10.0 | 3.5 – 5.0 | 8.0 – 10.0 |
NDC-I | Ø6.0 x 12.0 | 11.0 – 13.0 | 18.0 – 19.0 |
NDC-L | Ø8.0 x 15.0 | 19.0 – 21.0 | 27.0 – 29.0 |
Operate Band 30-35 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | N/A | N/A |
NDR-M | 8.0 x 3.0 x 3.0 | N/A | N/A |
NDR-I | 12.0 x 3.5 x 3.5 | 3.0 – 4.5 | 10.0 – 11.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 6.0 – 8.0 | 14.0 – 16.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | N/A | N/A |
NDC-M | Ø4.0 x 10.0 | 2.0 – 3.5 | 9.0 – 10.0 |
NDC-I | Ø6.0 x 12.0 | 9.0 – 11.0 | 18.0 – 20.0 |
NDC-L | Ø8.0 x 15.0 | 16.0 – 19.0 | 26.0 – 28.0 |
Parallel Actuation Distances

Operate Band 20-25 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | 1.0 – 3.0 | 4.0 – 5.0 |
NDR-M | 8.0 x 3.0 x 3.0 | 6.0 – 7.0 | 10.0 – 11.0 |
NDR-I | 12.0 x 3.5 x 3.5 | 10.0 – 11.0 | 14.0 – 16.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 14.0 – 15.0 | 19.0 – 20.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | 4.0 – 5.0 | 6.0 – 7.0 |
NDC-M | Ø4.0 x 10.0 | 9.0 – 10.0 | 13.0 – 14.0 |
NDC-I | Ø6.0 x 12.0 | 16.0 – 17.0 | 21.0 – 22.0 |
NDC-L | Ø8.0 x 15.0 | 23.0 – 25.0 | 29.0 – 30.0 |
Operate Band 25-30 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | 1.5 – 2.0 | 3.0 – 4.0 |
NDR-M | 8.0 x 3.0 x 3.0 | 5.0 – 6.0 | 8.0 – 9.0 |
NDR-I | 12.0 x 3.5 x 3.5 | 9.0 – 10.0 | 12.0 – 13.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 12.0 – 14.0 | 18.0 – 20.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | 3.0 – 4.0 | 6.0 – 7.0 |
NDC-M | Ø4.0 x 10.0 | 8.0 – 9.0 | 11.0 – 12.0 |
NDC-I | Ø6.0 x 12.0 | 14.0 – 16.0 | 20.0 – 21.0 |
NDC-L | Ø8.0 x 15.0 | 20.0 – 23.0 | 28.0 – 29.0 |
Operate Band 30-35 (AT)
Magnet | Dimensions | Operate Distance | Release Distance |
NDR-T | 4.0 x 1.5 x 1.5 | N/A | N/A |
NDR-S | 6.0 x 2.5 x 2.5 | 0.5 – 1.5 | 3.0 – 6.0 |
NDR-M | 8.0 x 3.0 x 3.0 | 4.0 – 5.0 | 8.0 – 10.0 |
NDR-I | 12.0 x 3.5 x 3.5 | 8.0 – 9.0 | 13.0 – 20.0 |
NDR-L | 19.0 x 4.0 x 4.0 | 12.0 – 13.0 | 19.0 – 21.0 |
NDC-T | Ø2.0 x 4.0 | N/A | N/A |
NDC-S | Ø3.0 x 7.0 | 2.0 – 3.0 | 6.0 – 9.0 |
NDC-M | Ø4.0 x 10.0 | 7.0 – 8.0 | 12.0 – 16.0 |
NDC-I | Ø6.0 x 12.0 | 13.0 – 14.0 | 20.0 – 24.0 |
NDC-L | Ø8.0 x 15.0 | 19.0 – 20.0 | 27.0 – 28.0 |
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