Frequency sensors measure the frequency of an electrical signal. Also known as frequency meters or referred to as a frequency sensor transducer, they are vital for equipment that is sensitive to frequency changes, or in machinery where damage would occur if the frequency fluctuated too greatly and went undetected, thus causing damage.

Frequency sensor suppliers offer several different kinds of frequency meters and sensors. The type you select will depend on your specific business requirements. You may want to ask yourself the following three questions when comparing frequency sensor providers and the products available for purchase:

1. What type of frequency sensor do you need to accurately measure and protect your equipment?

2. Will your frequency sensor transducer be monitoring single or multiple phases of electrical current?

3. Do you require an electronic readout or digital display of the electrical signal frequency for more detailed readings?

Action Steps
The best contacts and resources to help you get it done

Determine the type of frequency sensor you require to protect your equipment

Trip-point frequency sensors have fixed or adjustable trip points and continuously monitor electrical signals. When a specific tripping point is reached, the frequency sensor will automatically disconnect the device from a power source to avoid damage. Pass band frequency sensors can be fixed or adjustable and continuously monitor whether an electrical frequency is within an acceptable range. When a signal rises above or below the range, it automatically disconnects from the power source as well.

I recommend: Leach International manufactures a fixed pass band frequency sensor that has a sensing range of 320 to 480 Hz. ABB manufactures a series of adjustable trip-point frequency sensors.

Determine if your frequency sensor will be reading multiple phases or a single source of electricity

A frequency sensor detector can monitor equipment that has just one or multiple flows of electricity. The frequency meter or sensoring equipment you select will depend on how intricate your equipment or machinery is and how many different sources of power are required for it to operate correctly.

I recommend: CR Magnetics carries a series of analog and digital frequency transducers for single and three-phase detection purposes. Powertek's M100 series of frequency transducers measure frequency in single- and three-phase systems.

Compare digital frequency meters carried by frequency sensor suppliers

While analog frequency meters are available for purchase, you may require a more detailed reading. Digital frequency meters come in hand held and wall mount models and are also manufactured with three- and four-digit displays. The greater the display, the more accurate the measurement. The type you pick will depend on your monitoring and measurement needs.

I recommend: Nutronics India manufactures five different digital frequency meters that have either three- or four-digit readout displays. Galco Industrial Electronics sells various models manufactured by different companies.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Why monitor just one when you can multitask? Multifunctional frequency meters are available that measure more than just electrical signal frequency. They can also monitor voltage, current, power and even energy levels using the same measurement device.