APCI-3003 Appendix
Parameter
The parameters of a control comprise all fort he control process
required numeric values, e.g. for limit values and technological
number.
PCI bus
PCI bus is a fast local bus with a clock rate up to 33 MHz. This
bus is used for processing a great number of data. The PCI bus
is not limited like the ISA and EISA systems.
Protective circuitry
A protective circuitry of the active part is done in order to
protect the control electronic. The simplest protective circuitry
is the parallel switching of a resistance.
Protective diode
At the input of the integrated MOS (Metal Oxide Semi-
Conductor)-circuits used diodes, which operates at the permitted
input voltages in the reverse range, but at overvoltage in the
transition range and therefore protects the circuits against
damage.
Reference voltage
A point to which all further potentials of a series are referred
(often ground potential). In the field of control and regulation,
all voltages are measured against a reference voltage.
Reference voltage
Reference voltages are stable voltages that are used as reference
unit. From them voltages can be derived that are required for
example in current supplies and in other electronic circuitries.
Resolution
The smallest significant number to which a measurement can be
determined. For example a converter with 12-bit resolution can
resolve 1 part in 4096.
Scan mode
Scan modes are: Single software scan, single hardware triggered
scan, continuous software scan, continuous software scan with
timer delay, continuous hardware triggered scan and continuous
hardware triggered scan with timer delay.
Sensor
A device that responds to physical stimuli (heat, light, sound,
pressure, motion, etc.) and produces a corresponding electrical
output.
Sequence mode
A sequence consists of a certain number of acquisitions, and the
sequence mode defines the mode of acquisition (simple
sequence mode and sequence mode with delay)
Settling time
The time required, after application of a step input signal, for
the output voltage to settle and remain within a specified error
band around the final value. The settling time of a system
includes that of all of the components of the system.
Short circuit
A short circuit of two clamps of an electric switch is when the
concerning clamp voltage is zero.
Short circuit current
Short circuit current is the current between tow short-circuited
clamps.
Signal delay
The change of a signal affects the following circuitries with
finite velocity; the signal will be delayed. Besides the signal
delay times that are not wanted, the signal delay can be
extended by time switches and delay lines.
Simple mode
The software initializes and starts the A/D conversion and after
this step it reads the digital value of one or more channels.
Single Ended inputs
(SE)
An analog input with one input terminal whose value is
measured with respect to a common ground
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