APCI-3701 Glossary
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Typically the half-bridge transducer forms half of a Wheatstone
Bridge circuit which enables change from null to be readily
determined.
Impedance
The reciprocal of admittance. Admittance is the complex ratio
of the voltage across divided by the current flowing through a
device, circuit element, or network.
Inductive loads
The voltage over the inductor is U=L.(dI/dt), whereas L is the
inductivity and I is the current. If the current is switched on fast,
the voltage over the load can become very highly for a short
time.
Input impedance
The measured resistance and capacitance between the high and
low inputs of a circuit.
Input level
The input level is the logarithmic relation of two electric units
of the same type (voltage, current or power) at the signal input
of any receive device. The receive device is often a logic level
that refers to the input of the switch. The input voltage that
corresponds with logic “0” is here between 0 and 15 V, and the
one that corresponds with logic “1” is between 17 and 30 V.
Interrupt
A signal to the CPU indicating that the board detected the
occurrence of a specified condition or event.
Level
Logic levels are defined in order to process or show
information. In binary circuits voltages are used for digital units.
Only two voltage ranges represent information. These ranges
are defined with H (High) and L (Low). H represents the range
that is closer to Plus infinite; the H level is the digital 1. L
represents the range that is closer to Minus infinite; the L level
is the digital 0. The rising edge is the transition from the 0-state
to the 1-state and the falling edge is the transition from the 1-
state to the 0-state.
Limit value
Exceeding the limit values, even for just a short time, can lead
to the destruction or to a loss of functionality.
Low-pass filter
Transmitting all frequencies below a certain value
LVDT
= Linear Variable Differential Transformer
With the core in a central position the coupling from the
primary to each secondary is equal, so VA = VB and the output
V0 = 0. As the core is displaced, VA differs from VB in
proportion to the displacement hence V0 changes in magnitude
and phase in proportion to movement in either direction from
null.
MUX =
Multiplexer
An array of semiconductor or electromechanical switches with a
common output used for selecting one of a number of input
signals.
Noise immunity
Noise immunity is the ability of a device to work during an
electromagnetic interference without reduced functions.
Noise suppression
The suppression of undesirable electrical interferences to a
signal. Sources of noise include the ac power line, motors,
generators, transformers, fluorescent lights, CRT displays,
computers, electrical storms, welders, radio transmitters, and
others.
