Six factors that need attention to prevent pressure sensor problems

[Guide] If the pressure sensor is exposed to a manufacturing environment that exceeds the limits specified by the supplier during storage or assembly, the sensor will have problems. The following six factors are worth noting.

If the pressure sensor is exposed to a manufacturing environment that exceeds the limits specified by the supplier during storage or assembly, the sensor will have problems. The following six factors are worth noting:

1. Temperature

Excessive temperature is one of the common causes of many problems with pressure sensors, because pressure sensors have many components that can only work normally within the specified temperature range. During assembly, if the sensor is exposed to an environment outside these temperature ranges, it may be negatively affected.

For example, if the pressure sensor is installed close to the steam pipe that generates steam, the dynamic performance will be affected. The correct and simple solution is to move the sensor to a location far away from the steam line.

2. Voltage spikes

Voltage spikes refer to short-term voltage transients. Although this high-energy surge voltage lasts only a few milliseconds, it can still cause damage to the sensor. Unless the source of the voltage spike is very obvious, such as from lightning, it is extremely difficult to find. OEM engineers pay attention to potential failure risks in the entire manufacturing environment and surrounding areas. Timely communication with us helps to identify and eliminate such problems.

3. Fluorescent lighting

Fluorescent lamps require high-pressure arcs to break down argon and mercury when starting, so that the mercury is heated into a gaseous state. This starting voltage spike may pose a potential hazard to the pressure sensor. In addition, the magnetic field generated by the fluorescent lighting may also induce a voltage to act on the sensor wire, so that the control system may mistake it for the actual output signal. Therefore, the sensor must not be placed under or near the fluorescent lighting device.

4. EMI/RFI

Pressure sensors are used to convert pressure into electrical signals, so they are susceptible to electromagnetic radiation or electrical interference. Although sensor manufacturers have tried their best to ensure that the sensor is protected from the adverse effects of external interference, some specific sensor designs should reduce or avoid EMI/RFI (Electromagnetic Interference/Radio Frequency Interference) effects.

Other sources of EMI/RFI to avoid include contactors, power cords, computers, walkie-talkies, cell phones, and large machinery that generate varying magnetic fields. Common methods to reduce EMI/RFI interference include shielding, filtering and suppression. You can consult us for the correct precautions.

5. Shock and vibration

Shock and vibration can cause a variety of problems, such as dents in the housing, broken wires, cracked circuit boards, signal errors, intermittent failures, and shortened lifespan. In order to avoid shock and vibration in the assembly process, OEM manufacturers must first consider this potential problem in the designer, and then take measures to eliminate it.

The simple method is to install the sensor as far away as possible from obvious shock and vibration sources. Another possible solution is to use a vibro-isolator, depending on the installation method.

6. Overpressure

Whether it is at its own manufacturing site or at the user's place, once the OEM has completed the machine assembly, care should be taken to avoid overvoltage problems. There are many reasons for overvoltage, including water hammer effect, accidental heating of the system, and voltage stabilizer failure.

If the pressure value occasionally reaches the upper limit of the withstand pressure, the pressure sensor can still withstand and restore the original state. But when the pressure value reaches the burst pressure, this will cause the sensor diaphragm or housing to rupture, causing leakage. The pressure value between the upper limit of the withstand pressure and the rupture pressure may cause the diaphragm to deform, thereby causing output drift.

To avoid overvoltage, OEM engineers understand the dynamic performance of the system and the limits of the sensor. When designing, they need to grasp the interrelationships among system components such as pumps, control valves, balance valves, check valves, pressure switches, motors, compressors, and storage tanks.