With traditional pressure sensors, in the event of diaphragm damage the product can come into contact with actuation fluid. Diaphragm failure can remain undetected over a period of several production batches, causing contamination with corresponding losses in product value.The special “Sentinel DFI” (Diaphragm Failure Indication) technology offers a reliable remedy.A double diaphragm improves protection against contamination even in the event of a fracture of the outer diaphragm. But most importantly, with continuous electronic monitoring, diaphragm failure is immediately detected and actively reported by an alarm signal, so that the sensor can be replaced before the next production cycle.
Protection of high-value products against contamination and immediate alarm in case of diaphragm failure:
Processes with fast and extreme pressure changes may, in rare cases, cause diaphragms to fail. With conventional pressure sensors, the medium then comes into direct contact with the actuation fluid of the sensor. The use of “dry” sensors, which operate without actuation fluid, does not offer a solution as the product will come into contact with interior mechanical parts of the sensor, which are not sterilized. If the failure remains undetected, this can lead to several production batches of a high quality product becoming contaminated and unusable. High losses in value, loss of time and additional costs are possible consequences.
Sentinel DFI technology consists of an outer diaphragm (1), which is in contact with the product, and an inner diaphragm (2), which is in contact with the pressure actuation fluid of the sensor. Both are manufactured, heat-sterilized and placed on top of each other with high precision, and then a vacuum is created in the area between the two to form a singular unit. In the event of damage to the outer diaphragm, the second protective layer prevents contact between the product and the actuation fluid. The Sentinel DFI technology features a piezo transducer that monitors the vacuum via a channel (3).
In the event of a fracture of the outer or of both diaphragms, the vacuum is lost and an alarm signal is triggered automatically. This error signal makes it possible to replace the sensor before the next production cycle and thus protect the subsequent processes from contamination.