RS PRO Red LED Indicator Lamp, 24V dc, E5 Base, 6mm Diameter, 45mcd

Martindale TEK200 Non-Contact Voltage and Magnetic Field Detector

A non-contact voltage detector with the additional ability to detect magnetic fields, the TEK200 has audible warning and a self-test feature. Sleek in design and designed to be durable the detector can operate in an altitude of up to 2000m.
Suitable for permanent magnets and for indication of the polarity of machine windings, it has a magnetic sensitivity of ±10 mT. Indicating the operation of solenoid valves in pneumatic and hydraulic control equipment, testing relays or solenoids in a wide range of controls it has a wide variety of applications.

Features and Benefits:

• Senses AC voltages from 100 - 600V
• Detects electrical field
• Eliminates need for separate proving unit
• Self-testing
• Displays polarity of magnetic fields
• Powered by PP3 battery (RS Stock No. 394-9059)

How do magnetic field sensors and detectors work?

Magnetic field sensors are able to detect changes such as direction, strength or flux in a magnetic field. Magnetic field detectors are able to detect fields, such as unipolar, bipolar and electro-magnetic. There are many types of technology used for this and they all have different approaches. Some record the resistance, some have coils surrounding magnetic material, another measures fields against an internal magnet based response that runs through a fluxing set of parameters. Some devices contain switches, when the state of the switch is changed for example from open to closed, a magnetic field has been detected. The most commonly known technologies are Fluxgate, Hall Effect, Magnetoresistive, magnetoinductive and SQUID. (Superconducting quantum interference devices)