Switch and Sensor Basics
Throughout the Euroswitch range, products within each category are manufactured as either simple switches or sensors. Switches are available as NO (normally open) or NC (normally closed), meaning they either open or close an electrical circuit. Also available are SPDT (single-pole double-throw) switches that allow for NO, NC, or both, making the range highly versatile and suitable for most electrical circuits. A typical application of such a switch can either stop a machine or alert the operator to a fault in the system—such as low fluid levels or excessive system temperatures.
Cheryl Johnson of Hydrasales says, “It is all about their investment in research and development. Many leading manufacturers task their highly experienced teams to conceptualise solutions and help minimise and manage system failures.”
Euroswitch implements management systems certified to UNI EN ISO 9001:2015 for quality, UNI EN ISO 14001:2015 for environmental protection, and UNI EN 45001:2018 for health and safety at work.
Sensors enable monitoring via transmitters, transducers, or resistive sensors, allowing operators or maintenance teams to receive live readings of temperature, level, or pressure—whether displayed at the operator’s station or linked to an industrial network. Sensors are vital for providing the required information in automated operations, and system engineers should adopt and implement such protective measures.
Is It Cost-Effective and Important as a Preventive Measure?
Some may think that the inclusion of sensors or switches is costly and complicated—but it is not.
Using an example of a simple low fluid level switch, it is relatively inexpensive at R1200 to R1500. This can save thousands of Rands in maintenance. A low-level indicator is recommended and can be included into the hydraulic tank and linked to the electrical circuit. Typically, it will prevent system start-up if a low fluid level is measured or reached. This is a very basic yet crucial requirement of a hard-working system. Low levels of fluid can easily heat a system, or worse, starve a pump. It has to be noted that hydraulic pumps can easily be one of the costliest components of an hydraulic circuit, where the lack of sufficient oil can cause irreparable damage within a short period of time.
Pressure Switches and Their Industry Applications
Maintaining required pressure levels—and ensuring that systems do not exceed them—is critical to the successful operation of a hydraulic system. Pressure switches and transducers are widely used across industries, including:
- HVAC systems, gas cylinders, and air pumps: to monitor and control air pressure.
- Engines: oil pressure switches act as actuators or sensors to detect when oil pressure drops below a preset level.
- Furnaces: pressure switches serve as safety devices for industrial and residential applications.
- Borehole and water pump systems: maintain sufficient water supply in residential and commercial buildings.
- Vacuum systems: vacuum pressure switches measure negative pressure and are found in boilers, air compressors, and transmission systems.
How Hot Is Too Hot?
Heat plays an equally important role in lubricated systems. When temperature increases, the lubricant becomes thinner and viscosity decreases. Conversely, as temperature decreases, the lubricant thickens and viscosity increases, making it harder to pour or pump.
A system may require heating or cooling to maintain suitable operating temperatures. Excessive heat can over-thin the oil, resulting in surface-on-surface wear. Without correct viscosity, increased wear rates lead to reduced lifespan or component failure.
A simple solution is the addition of a thermostat to an air-blast cooler. When the preset temperature is reached, the cooler is activated; when the temperature drops below the lower limit, it switches off—achieving efficient and automatic thermal regulation.
Beyond hydraulic systems, heat control and monitoring are vital in numerous industries, including radiator and heat-exchanger systems, lubrication systems, automotive, refrigeration, heating systems, coffee-making machines, vending machines, and household appliances.
