Various factors impact the selection and long term use of pressure sensors and transducers in water measurement applications. AST manufactures various products with design features to offer excellent accuracy and long term stability. Below is some basic information to review before making a decision on the type of pressure sensor technology as well as the electrical and mechanical features required.
A pressure sensing element will come in contact with varying pH levels, depending on the type of water, chemicals added and the quality of the water purification process. AST packages pressure sensors using Krystal Bond Technology and our one piece, 316L stainless steel sensing element. 316L SS offers excellent media compatibility for residential and commercial water applications and is NSF61 compliant. For applications such as salt water in water maker equipment, AST offer Inconel 718 material and Hastelloy C276. The sensor diaphragm and fitting are all manufactured by machining the same piece of metal with no welds or O-rings.
The opening and closing of valves in a system can cause a pressure transient within a water pump above the measurement range in a shock-wave. AST installs an internal, stainless steel restrictor plug. This reduces the inside diameter hole to 0.040." By reducing the ID, the pressure spike hits the face of the snubber and feeds through the hole at a slower pace. The plug, also termed snubber, dampens the spike to continue sensor operation.
Rain, ice, dust, and pressure washers can cause water to seep into sensor housings and cause the electronics to short. AST offers sealed gauge reference pressure sensors to protect the electronics from these conditions.
Improper grounding and lightning strikes can cause electrical failures of pressure sensors, as a result of isolation failure. AST can include custom electronics and a sensing element to withstand 500VDC isolation to work in extreme electrical conditions
Depending on distance and environment, certain output signals can experience signal loss or generate noisy signals. AST recommends 4-20mA output signals for transmission lengths greater than 15 feet in environments with electrical noise.
4-20mA output signal
Packard Metripack 150 electrical connection
316L SS with internal restrictor
UL/cUL508 & CE EN61326
In summary, AST pressure sensors can be built to last through the rugged conditions common to water systems. By reviewing the application and environment of the sensor, AST can provide a solution.
Contact us with more details on your requirements and we can assist to develop a solution.