Radiation Tolerant Sensors

The Authority has a requirement for sensors that are capable of operating safely and reliably within defined radiation exposed environments associated with nuclear operations. The requirement is driven by:

∙ Nuclear safety and operational assurance

∙ Asset integrity and reliability

∙ The need for predictable performance under radiation exposure

The Authority’s need is outcome based and does not specify any particular manufacturer, brand, or proprietary solution.

The Authority requires devices that have been independently tested to exceed a Dose of 1 x 106 Gray. The estimated requirement is for 1,224 Sensors with:

∙ 18mm diameter sensor – 18mm threaded barrel, to be supplied with 2 off M18 x 1mm locknuts

∙ Flush fitting

∙ NAMUR two wire Inductive Sensor - DC 2-wire, nom. 8.2 VDC, Output acc. to EN 60947-5-6 (NAMUR)

∙ Nominal Switching Distance 5mm - 10mm

∙ Sensor head length - Not to exceed 65mm

∙ Fitted electrical Lead (Not M12 connector) – Minimum lead length of 2 metres

∙ ATEX category II 1 G, Ex zone 0

∙ ATEX category II 1 D, Ex zone 20

∙ SIL2 (Low Demand Mode) acc. to IEC 61508, PL c acc. to ISO 13849-1 with HFT0

∙ SIL3 (All Demand Mode) acc. to IEC 61508, PL e acc. to ISO 13849-1 with redundant configuration HFT1

∙ Protection Class IP67

The Authority requires that supplied sensors are to contain Semi-Conductor (SMD/SMT) devices from the same Semi-Conductor Component Manufacture production batch.

An Initial Sensor manufacturing batch of a minimum of 11 Sensors is required to allow for Sellafield Limited initiated Third Party Radiation Tolerance Testing.

The remaining Semi-Conductor devices (the same Reel) are to be retained awaiting the conclusion of the Third Party Radiation Tolerance Testing.

On conclusion of Radiation Tolerance Testing, if Sellafield Limited deem the sensors to be acceptable, the balance of stated Order Total are to be manufactured from the same SMD/SMT component Reel as those sensors manufactured for the purpose of the test (≥11 sensors). If, the first batch (11 off) sensors are not acceptable to Sellafield limited, a further 11 off sensors are to be produced to allow for repeat Radiation Tolerance Testing, the semi-conductor component requirements remain as above.

The Sensor Manufacturer is to create a specific product Part Number for the Authority.

Sellafield Ltd Quality Grade 04 for sensors produced for testing purposes, Quality Grade 03 for all other supplied sensors.