What is the Difference between a Pressure Switch and a Limit Switch?
Limit switches and pressure switches are both used to control the safety of mechanical movement.
Limit switches are mainly used to detect or control the stroke of mechanical equipment. Ensure that the equipment moves within the specified range to avoid misoperation or damage during the process. For example, when the robot arm reaches the specified position, the limit switch will stop the movement of the robot arm.
Pressure switches are mainly used to detect or control the pressure state. For example, in a hydraulic system, when the oil pressure is lower than a certain value, the pressure switch will open. Close the fluid control line to avoid damage to equipment or personnel.
Therefore, the applications of limit switches and pressure switches in system control are different. They both have their unique functions and roles.
Key Points for Selecting Baffle Flow Switches
Flow threshold setting
Key parameters: trigger flow (such as 1L/min), reset flow (usually 80% of the trigger flow).
Selection tool: Determine the model by combining the flow-pressure drop curve provided by the supplier with the pipe diameter and medium viscosity.
Material and protection level
Media compatibility:
Ordinary waterway: brass/stainless steel body + EPDM sealing ring.
Corrosive media: 316L stainless steel + PTFE sealing ring.
Protection level: IP65 (dustproof and waterproof) is a general standard. IP67/IP68 is required for outdoor applications.
Output signal type
Mechanical switch: Direct drive contactor or relay, suitable for traditional control systems.
Electrical signal output: Optional dry contact (NO/NC), PNP/NPN transistor output, compatible with PLC/DCS system.
