Glossary / Index
A
Drop-out value
indicates the voltage, current or flow value at which a reed switch or reed relay opens again. This is measured in V, A or AW. Response time is the time in ms from switching on the coil voltage until the reed contact switches. Pick-up voltage is the voltage at the coil of a reed relay at which the switching contacts switch.
indicates the voltage, current or flow value at which a reed switch or reed relay opens again. This is measured in V, A or AW. Response time is the time in ms from switching on the coil voltage until the reed contact switches. Pick-up voltage is the voltage at the coil of a reed relay at which the switching contacts switch.
Response time
is the time in ms from switching on the coil voltage to switching the reed contact.
is the time in ms from switching on the coil voltage to switching the reed contact.
Pull-in voltage
is the voltage at the coil of a reed relay at which the switching contacts switch.
is the voltage at the coil of a reed relay at which the switching contacts switch.
Operating temperature
determines the temperature range in which a reed switch, reed sensor or reed relay operates safely. Our specifications in the data sheets are for an ambient temperature of 20°C.
determines the temperature range in which a reed switch, reed sensor or reed relay operates safely. Our specifications in the data sheets are for an ambient temperature of 20°C.
AT value (Ampere-turns)
is the English designation of the AW value. It defines the magnetic sensitivity of a reed switch. It is calculated from the number of turns of the magnetic coil multiplied by the current flow through the coil at which the reed contact switches.
is the English designation of the AW value. It defines the magnetic sensitivity of a reed switch. It is calculated from the number of turns of the magnetic coil multiplied by the current flow through the coil at which the reed contact switches.
AW value (ampere-turns)
is the German designation of the AT value
is the German designation of the AT value
D
Breakdown voltage
defines the voltage above which a breakdown occurs between the open contact blades of the reed switch.
defines the voltage above which a breakdown occurs between the open contact blades of the reed switch.
E
Stainless steel
is a term for unalloyed and alloyed steels with a special degree of purity. It is often used as a housing material for products that require special properties, such as high temperature resistance and high chemical resistance.
is a term for unalloyed and alloyed steels with a special degree of purity. It is often used as a housing material for products that require special properties, such as high temperature resistance and high chemical resistance.
Melting zone
is the area of the reed switch in which the connecting wires or contact tabs are melted into the glass body.
is the area of the reed switch in which the connecting wires or contact tabs are melted into the glass body.
Electrostatic shield
prevents the crosstalk of signals between the coil and one or more contacts in a relay. The shield is usually made of copper and is led out at one or more points.
prevents the crosstalk of signals between the coil and one or more contacts in a relay. The shield is usually made of copper and is led out at one or more points.
Sensitivity (magnetic)
refers to the pick-up and drop-out point of a reed switch and is usually specified in AW (AT).
refers to the pick-up and drop-out point of a reed switch and is usually specified in AW (AT).
Demagnetization
is the reduction of the magnetic force of a magnet. This is achieved by an opposing field, the influence of temperature or radioactive radiation.
is the reduction of the magnetic force of a magnet. This is achieved by an opposing field, the influence of temperature or radioactive radiation.
H
Holding voltage
is the voltage on a relay coil that is required to keep a reed switch closed.
is the voltage on a relay coil that is required to keep a reed switch closed.
Holding current
is the current through a relay coil that is required to keep a reed switch closed.
is the current through a relay coil that is required to keep a reed switch closed.
HG-wetted switches
are reed switches with a thin mercury film over the contact blades. This achieves bounce-free switching, a high load capacity with a long service life and a low contact resistance that remains constant over the service life.
are reed switches with a thin mercury film over the contact blades. This achieves bounce-free switching, a high load capacity with a long service life and a low contact resistance that remains constant over the service life.
Highly insulated relays
have a very high insulation resistance of up to 100 TOhm. Among other things, they are used for switching voltages in the nanovolt range or for switching femto amps.
have a very high insulation resistance of up to 100 TOhm. Among other things, they are used for switching voltages in the nanovolt range or for switching femto amps.
Hysteresis
of a reed switch is the difference between the response value and the drop-out value in a test coil. The hysteresis is often also specified as the ratio of the drop-out value to the response value in %. The hysteresis depends on the design of the reed switch. (contact tongue coating, coating thickness, contact tongue geometry).
of a reed switch is the difference between the response value and the drop-out value in a test coil. The hysteresis is often also specified as the ratio of the drop-out value to the response value in %. The hysteresis depends on the design of the reed switch. (contact tongue coating, coating thickness, contact tongue geometry).
I
IP protection classes
The IP codes define the degree of protection against the ingress of foreign bodies and water. This allows you to assess how suitable this product is for different environments.
The IP codes define the degree of protection against the ingress of foreign bodies and water. This allows you to assess how suitable this product is for different environments.
Insulation voltage
is the voltage value that defines the insulation of an open contact, between two contacts, between contact and winding or between contact and shielding or conductive housing.
is the voltage value that defines the insulation of an open contact, between two contacts, between contact and winding or between contact and shielding or conductive housing.
Insulation resistance
is the DC resistance in ohms, measured at the open contact or, in the case of a relay, also between the contact and winding or contact and shield. The measurement is usually carried out at 100 V/DC.
is the DC resistance in ohms, measured at the open contact or, in the case of a relay, also between the contact and winding or contact and shield. The measurement is usually carried out at 100 V/DC.
K
Capacitance
of a reed switch is measured at the open contacts. The values are in the range of 0.1 ... 1.0 pF. The low contact capacitance is a special feature of reed contacts.
of a reed switch is measured at the open contacts. The values are in the range of 0.1 ... 1.0 pF. The low contact capacitance is a special feature of reed contacts.
Contact
designates a structure with contact tongues that are necessary for the function of a reed switch or electromechanical relay. A contact always has at least two contact blades, which can be symmetrical or asymmetrical in the glass body.
designates a structure with contact tongues that are necessary for the function of a reed switch or electromechanical relay. A contact always has at least two contact blades, which can be symmetrical or asymmetrical in the glass body.
Contact, load capacity
defines the permissible switching capacity, which is the product of switching current and switching voltage.
defines the permissible switching capacity, which is the product of switching current and switching voltage.
Contact form
Reed contacts and reed sensors have different contact types (normally open, normally closed, changeover contact, ...)
Reed contacts and reed sensors have different contact types (normally open, normally closed, changeover contact, ...)
Contact, gap distance
is the distance between the switching tongues in the open state.
is the distance between the switching tongues in the open state.
Contact current load
specifies the current that the reed switch can switch without being damaged or experiencing a reduction in service life.
specifies the current that the reed switch can switch without being damaged or experiencing a reduction in service life.
Contact form
describes the contact variant used (form A: normally open contact, form B: normally closed contact, form C: changeover contact)
describes the contact variant used (form A: normally open contact, form B: normally closed contact, form C: changeover contact)
Contact sticking
is the situation in which the contact blades are permanently welded together due to electrical overload of the reed switch. As a result, the switching function is no longer available and the contact has permanent continuity.
is the situation in which the contact blades are permanently welded together due to electrical overload of the reed switch. As a result, the switching function is no longer available and the contact has permanent continuity.
Contact resistance
is the electrical resistance of a closed switch. It is measured after the contact has safely closed. The contact resistance of a reed switch is typically between 50 and 100 mOhm.
is the electrical resistance of a closed switch. It is measured after the contact has safely closed. The contact resistance of a reed switch is typically between 50 and 100 mOhm.
Contact protection measures
are circuit measures to limit the current or voltage during the switching process.
are circuit measures to limit the current or voltage during the switching process.
Plastic housing
made of various materials such as PA, PP, PBT, etc. serve as a protective housing for the switching elements.
made of various materials such as PA, PP, PBT, etc. serve as a protective housing for the switching elements.
L
Load-free switching
means closing and opening a reed switch with negligibly low current and voltage.
means closing and opening a reed switch with negligibly low current and voltage.
Leakage current
is an unintentional fault current via the open contact or between the contact and the winding.
is an unintentional fault current via the open contact or between the contact and the winding.
M
Magnet
is a body that is surrounded by a permanent magnetic field. If it is brought close to a reed switch, the reed contact switches as a result of the magnetic flux (contactless switching).
is a body that is surrounded by a permanent magnetic field. If it is brought close to a reed switch, the reed contact switches as a result of the magnetic flux (contactless switching).
Magnetic field lines
indicate the direction and magnitude of the magnetic field. Magnetic field lines can be represented as concentric circles that emerge from the north pole of the magnet and enter the south pole.
indicate the direction and magnitude of the magnetic field. Magnetic field lines can be represented as concentric circles that emerge from the north pole of the magnet and enter the south pole.
Magnetic pole
is located at the end of a magnet. This is where the field line density is greatest and this is also where the magnetic force is strongest (north and south pole of a magnet).
is located at the end of a magnet. This is where the field line density is greatest and this is also where the magnetic force is strongest (north and south pole of a magnet).
Magnetic shield
consists of ferromagnetic (magnetically conductive) material and is usually located above the coil of a relay. This increases the magnetic flux within the winding and largely shields it from the outside. It contributes to the safe switching function and at the same time provides protection against external magnetic fields.
consists of ferromagnetic (magnetically conductive) material and is usually located above the coil of a relay. This increases the magnetic flux within the winding and largely shields it from the outside. It contributes to the safe switching function and at the same time provides protection against external magnetic fields.
N
Nominal voltage
is the defined, ideal voltage for the operation of a coil (a relay).
is the defined, ideal voltage for the operation of a coil (a relay).
O
Ohm's law
is defined as I=U/R. The electric current I is determined as the quotient of the applied voltage U and the resistance R in the circuit.
is defined as I=U/R. The electric current I is determined as the quotient of the applied voltage U and the resistance R in the circuit.
P
Paddle
is also known as the switching tongue of a reed switch. At least 2 paddles are always required to realize a switching element.
is also known as the switching tongue of a reed switch. At least 2 paddles are always required to realize a switching element.
R
Grid dimension
defines the distance between the individual connection pins, e.g. for a relay. Units: Inch or mm.
defines the distance between the individual connection pins, e.g. for a relay. Units: Inch or mm.
Reed relay
is a relay based on a reed contact as a switching element. One or more reed contacts are located inside the coil. When the rated voltage is applied, the coil generates a magnetic field, causing the reed contact to switch.
is a relay based on a reed contact as a switching element. One or more reed contacts are located inside the coil. When the rated voltage is applied, the coil generates a magnetic field, causing the reed contact to switch.
Reed switch
is a magnetically actuated switching contact. Here, 2 contact tongues are hermetically sealed in a glass tube with an inert gas filling.
is a magnetically actuated switching contact. Here, 2 contact tongues are hermetically sealed in a glass tube with an inert gas filling.
Reed sensor
is a reed contact encapsulated in a housing with connecting wires or connectors. There are various housing shapes and different housing materials. Reed sensors are mostly used as position sensors.
is a reed contact encapsulated in a housing with connecting wires or connectors. There are various housing shapes and different housing materials. Reed sensors are mostly used as position sensors.
Relay
is an electrical switching element with a control circuit and a load circuit. The control and load circuits are electrically isolated from each other. An armature is actuated by a magnetic field generated by a coil, which opens or closes the contacts in the load circuit. This allows large voltages and currents to be switched with a low control voltage.
is an electrical switching element with a control circuit and a load circuit. The control and load circuits are electrically isolated from each other. An armature is actuated by a magnetic field generated by a coil, which opens or closes the contacts in the load circuit. This allows large voltages and currents to be switched with a low control voltage.
Resonant frequency
specifies the frequency at which the contact tongues of the open reed contact tend to vibrate mechanically and close unintentionally. These vibrations can also permanently damage or destroy the reed switch. It varies depending on the reed contact used. A reed switch with a glass body length of approx. 14 mm, for example, has a resonance frequency of approx. 5000 Hz.
specifies the frequency at which the contact tongues of the open reed contact tend to vibrate mechanically and close unintentionally. These vibrations can also permanently damage or destroy the reed switch. It varies depending on the reed contact used. A reed switch with a glass body length of approx. 14 mm, for example, has a resonance frequency of approx. 5000 Hz.
RoHS
is an abbreviation for "Restriction of (the use of certain) Hazardous Substances in electrical and electronic Equipment". In German: Restriction of the use of certain hazardous substances in electrical and electronic equipment. The aim is to protect human health and the environment. These include, for example: lead in soldered joints, flame retardants in cable insulation and much more.
is an abbreviation for "Restriction of (the use of certain) Hazardous Substances in electrical and electronic Equipment". In German: Restriction of the use of certain hazardous substances in electrical and electronic equipment. The aim is to protect human health and the environment. These include, for example: lead in soldered joints, flame retardants in cable insulation and much more.
S
Switching distance
is the distance in mm between the reed sensor and the actuating magnet at which a reed sensor switches.
is the distance in mm between the reed sensor and the actuating magnet at which a reed sensor switches.
Switching hysteresis
is the difference between the switch-on and switch-off points. It can refer to the switching distances of the reed sensor or to the response and drop-out values of the relay. It can be specified in mm, V or as a ratio in %.
is the difference between the switch-on and switch-off points. It can refer to the switching distances of the reed sensor or to the response and drop-out values of the relay. It can be specified in mm, V or as a ratio in %.
Switching voltage
The switching voltage is the maximum permissible voltage that a reed contact can safely switch. This voltage must not be exceeded, not even for a short time.
The switching voltage is the maximum permissible voltage that a reed contact can safely switch. This voltage must not be exceeded, not even for a short time.
Closing time / response time
is the measured time between the application of the rated voltage to the coil and the closing of a switch, including bouncing.
is the measured time between the application of the rated voltage to the coil and the closing of a switch, including bouncing.
Protective circuit
for reed contacts and reed sensors protects reed contacts or reed sensors against overvoltage or overcurrent.
for reed contacts and reed sensors protects reed contacts or reed sensors against overvoltage or overcurrent.
Coil
generates a magnetic field when a voltage is applied as a result of the current flow. This is used to switch reed contacts (e.g. in a relay). The winding is usually made of enameled copper wire. It is possible to mount the winding on a coil carrier / coil former or as a self-supporting coil without a coil former.
generates a magnetic field when a voltage is applied as a result of the current flow. This is used to switch reed contacts (e.g. in a relay). The winding is usually made of enameled copper wire. It is possible to mount the winding on a coil carrier / coil former or as a self-supporting coil without a coil former.
Coilformers
are wound with copper wire to generate the magnetic field in a relay.
are wound with copper wire to generate the magnetic field in a relay.
Riser tube / slide tube
The riser tube or slide tube is the part of a float switch along which the magnetic float moves.
The riser tube or slide tube is the part of a float switch along which the magnetic float moves.
Current
is the magnitude of the electron current in a closed circuit, measured in amperes (unit A).
is the magnitude of the electron current in a closed circuit, measured in amperes (unit A).
Current, AC
is the alternating current in a closed circuit. The instantaneous value changes periodically (usually following a sinusoidal curve).
is the alternating current in a closed circuit. The instantaneous value changes periodically (usually following a sinusoidal curve).
Current, DC
is direct current that always flows in one direction, usually generated by a direct voltage source or a battery.
is direct current that always flows in one direction, usually generated by a direct voltage source or a battery.
T
Temperature coefficient
indicates the change in remanence and coercivity of magnetic materials as a function of temperature.
indicates the change in remanence and coercivity of magnetic materials as a function of temperature.
Transport current
is the current that can still be safely conducted via a closed contact without damaging the contact.
is the current that can still be safely conducted via a closed contact without damaging the contact.
U
Overexcitation
specifies the magnetic energy (in AW or mT) that is added after closing a reed switch in order to be able to carry out measurements on the contact. Contact resistances are normally measured with 25% overexcitation.
specifies the magnetic energy (in AW or mT) that is added after closing a reed switch in order to be able to carry out measurements on the contact. Contact resistances are normally measured with 25% overexcitation.
W
Alternating current
refers to a current that constantly changes its direction and magnitude (from positive to negative, often following a sinusoidal curve).
refers to a current that constantly changes its direction and magnitude (from positive to negative, often following a sinusoidal curve).
Resistor
is an electrical component that can limit the current flow in a closed circuit in a defined manner.
is an electrical component that can limit the current flow in a closed circuit in a defined manner.