What Factors Cause Pressure Sensor Malfunction and Failing

In the use of the pressure sensor, some factors will easily cause malfunction or failing to the sensor if these factors are not be avoided. This article summarizes six factors that are prone to pressure sensor failures, helping users solve malfunction and avoid malfunction in a timely manner.

• Temperature cause malfunction to pressure sensor
  

Excessive temperature is one of the common causes for many malfunction to pressure sensors, because many components in the pressure sensor can only work within the specified temperature range. During assembly, if the pressure sensor is exposed to an environment outside the operating temperature range, it is highly likely to be adversely affected.
For example, if the pressure sensor is installed close to the steam line that produces steam, its dynamic performance will be affected. A correct and simple solution is to transfer the pressure sensor to a location far from the steam line.

• Voltage spike cause malfunction to pressure sensor
  

Voltage spike is a short-lived voltage transient phenomenon. Although this high-energy surge voltage lasts only a few milliseconds, it still will cause damage to the pressure sensor. Unless the voltage spikes are very visible, such as spikes from lightning, it is extremely difficult to find. Pay attention to the entire manufacturing environment and the surrounding potential failure risks and eliminate such malfunction in the design and production of pressure sensors.

• Fluorescent lighting cause malfunction to pressure sensor
  

Fluorescent lamps require a high voltage to generate an arc to break through argon and mercury at startup, thereby heating the mercury into a gaseous state. This startup voltage spike can pose a potential hazard to the pressure sensor. In addition, the magnetic field generated by fluorescent illumination will also cause an induced voltage to act on the sensor wires, which will cause the control system to mistake it for the actual output signal. Therefore, the pressure sensor must be placed under or near the fluorescent lighting device.

• EMI/RFI cause malfunction to pressure sensor
  

Pressure sensors are used to convert pressure into electrical signals so they are susceptible to electromagnetic radiation or electrical interference. While the pressure sensor has ensured that it is protected from external interference when manufacturing, some specific pressure sensors need be designed to reduce or avoid the effects of EMI/RFI (electromagnetic interference/radio frequency interference).
Other sources of EMI/RFI that need to be avoided include contactors, power cords, computers, walkie-talkies, cell phones, and large machines that produce varying magnetic fields. The most common methods for reducing EMI/RFI interference are shielding, filtering, and suppression.

• Shock and vibration cause malfunction to pressure sensor
  

Shock and vibration will cause malfunction such as casing sag, broken wire, board breakage, signal errors, intermittent faults, and shorten life. To avoid shock and vibration during pressure sensor assembly, when designing the pressure sensor, this potential problem must be considered and take means to eliminate it.
The easiest way is to install the pressure sensor as far as possible from the obvious shock and vibration sources. Another possible solution is to use a vibrating isolator, which is depends on its installation.

• Pressure overload cause malfunction to pressure sensor
  

In any application environment, we should pay attention to the pressure overload. There are many reasons for pressure overload, including water hammer effects, system accidental heating, stabilizer failures, and so on.
If the pressure value occasionally reaches the upper pressure limit, the pressure sensor can withstand and return to its original state. However, when the pressure value reaches the rupture pressure, which will cause the diaphragm or casing of the pressure sensor to rupture, causing leakage. The pressure value between the upper pressure limit and the burst pressure will cause permanent deformation to the diaphragm, then causing output drift.
In order to avoid pressure overload, the user must understand the dynamic performance of the system and the limits of the pressure sensor in the use. In addition, the relationship between the components of the pump, control valve, balancing valve, check valve, pressure switch, motor, compressor and storage tank must be mastered.