Products FAQ

FAQ about our products

Here you will find answers to frequently asked questions about Reed sensors, Hall sensors, magnets und cable groups, offered by masetec.

Reed sensors / switches

Most reed switches / sensors are so called SPST-NO (Single-Pole-SingleThrow-Normally-Open) types and are also called Form-A switches (normally open contact). However, many Reed-based applications require an SPST-NC (Single-Pole-Single-Throw-Normally-Closed) or Form-B (normally closed contact). In addition, SPDT (Single-Pole-Double-Throw) or Form-C (changeover contacts) are indispensable in many applications. In a few products bistable or also Form-E or Latching called switches are used.

Sure, but due to the different sizes not all shapes are feasible for each of the masetec sensors.

This is of course the most important question because with this knowledge countless applications can be opened.

Two contact tongues consisting of ferromagnetic material are hermetically sealed in a glass tube under an inert atmosphere (e.g. nitrogen). After the melting process, the overlapping contact tabs inside the glass body form an air gap in the contact area. For a better switching behavior, the two tabs are coated with ruthenium, rhodium or iridium in the so-called contact zone. The clou is of course that with a sufficiently strong magnetic field the two contact tongues take on an opposite polarity and thus close the contact

Good question! A reed switch built into a housing is usually called a reed sensor, so the unbuilt reed is the switch.

Oh yes! Often there is nothing else behind terms like magnetic sensor, magnetic switch, window contact, position sensor and many others like a Reed sensor or switch.

A lot! Be it the general contactless switching, the fact that no supply current is required, that apart from small exceptions no minimum current is needed, that the contact resistance is 50 – 200 milliohm and that the lifetime at signal load is up to 1 billion switching cycles are probably the most important advantages.

Where are they missing? We are honest and do not want to gloss over anything. As explained above, it is a glass component and that is of course always a weak point if it is not handled properly. But that is what we are here for. We offer complete plug & play solutions to reduce risks. And of course we do not sell you a Reed sensor or switch if we are not convinced. And maybe we have other solutions besides reed based sensors.

Pay attention! AT stands for Ampere Turns and is in the reed world the most important value which defines the sensitivity and the switching distance. Attention often an AT value of e.g. 10-15AT is equated with a switching distance of 10-15mm which is absolutely wrong. The sensitivity of reed switches is determined in predefined coils. By applying a voltage to the coil (current flow) with a defined number of coil turns a magnetic field is generated. If I increase this current until the contact closes I have determined the sensitivity (A x T). If I reduce this current until the contact opens again, the result is the drop value.

Watch out, now it gets tricky! A high AT value e.g. 40-45AT means a low or low sensitivity (small switching distance) and therefore a value of e.g. 10-15AT has a higher sensitivity (high switching distance). Got it?

This is also possible and of course we help to define exactly this value in advance.

Right! This is the hysteresis and is nothing else than the difference between the suit and waste value described above.

This may be possible under certain circumstances but requires prior testing of the application.

Of course we know that every application requires different spacing. To generate these, we can either play with the AW value, use a stronger or weaker magnet or even adjust the magnet material. Also a revision of the position of the magnet to the Reed could lead to the desired goal. Here you can inform yourself in the download area about the different approaches and the resulting changes of the circuit.

Very simple! It’s not possible, it doesn’t exist or at least we try to make a lot of things possible and not to fob you off with “standard products”. Customer-specific solutions are very important to us!

Unfortunately no or at least this is dangerous. In Reed technology, as in their fields, they also try to avoid a simple changeover from one manufacturer to another. Here it depends on many things like the number of windings of the respective test coil. A coil with 5,000 turns has a different value than one with 10,000 turns.

Very simple, either we can deduce from the data sheet of your current supplier which AW value fits or just send us 5-10 samples and we can measure them and define the appropriate AW value of masetec. Of course transparent!

Once it is defined in your application, it will definitely be defined in all our standard sensors as well. But for special solutions or customized sensors we choose the Reed Switch that fits your application. Be it from KOFU, Standex, Littelfuse or RZMKP.

Hall sensors

Yes, Hall sensors must be protected against EDI/RFI.

Yes, Hall sensors require a power circuit and a driver.

Yes, because in the vicinity of a magnetic field they produce only a weak signal in millivolt strength. Therefore the signal must be amplified and fed into a circuit.

A semiconductor material placed near a magnetic field generates voltage proportional to the strength of the magnetic field.

The opening time of a Hall sensor is usually 5 µs.

Hall sensors usually have a resistance of more than 200 Ohm.

Magnets

You can obtain all materials like NdFeB, SmCo, AlNiCo and ferrites in all forms from us.

In our download area you will find an overview of exactly this topic.

Here you can also use our selection guide in the download area to find out about the differences.

Absolutely! That is exactly what we are strong in. Be it magnetic couplings, magnets in a housing for easy mounting, pot and hook magnets and and and. Just tell us what you need and we will take care of it.

Some things, to be honest. A NdFeB magnet, for example, is not equal to a NdFeB magnet. Here there are clear definitions with regard to strength and temperature resistance. You can find more information on this in the download area. But of course we will be happy to help you find the right magnet for your application.

Not a problem either. We only need a few samples, analyze them and then make you an appropriate offer.

Very different. Our selection guide also provides some insight into the cost structure of the different materials.

NdFeB in terms of volume or size.

According to our opinion AlNiCo, because they can be easily demagnetized by wrong handling and storage.

We ask you to check our warnings, which you will also find in the download area.

Cable assemblies or modules

If that is what you want: of course. But unfortunately, some manufacturers are quite inflexible regarding minimum quantities, especially when it comes to low demand, and of course there is an alternative for almost every connector, which may have an interesting solution in terms of availability and price. We will be happy to present this solution to you.