KAL EQUIP KAL 3840 - Manual (Page 67)

Scan Tool A device that interfaces with and communicates information on a data link.
Sample A reading taken from an electrical signal. A waveform is created f rom a successive
number of samples.
Sampling Rate The number of readings taken from an electrical signal every second.
Saturated Driver Fuel injection circuit that maintains the same voltage level throughout its on-time.
Secondary Pickup A n accessory t hat can be clamped on t he high volt age coil wire used to measure
secondary ignition patterns.
Shielded Test Lead A test lead that is surrounded by a conductive screen to protect the measurement signal
against environmental influences, such as electrical noise or radiation.
Shift Solenoid A device that controls shifting in an automatic transmission.
Single Shot A signal measured by an oscilloscope t hat only occurs once (also called a transient
event).
Spark Advance The relationship between the ignition timing and top dead center (DTC).
Spike A (high) voltage pulse during a short period of time (sharp pulse).
Throttle A valve for regulating the supply of a fluid, usually air or a fuel/air mixture, to an engine.
Time Base The time defined per horizontal division on the display.
Trace The displayed waveform that shows the variations of the input signal as a function of
time.
Trigger Determines the beginning point of a waveform.
Trigger Level The voltage level that a waveform must reach to start display.
Trigger Slope The voltage direction that a waveform must have to start display. A positive Slope
requires the voltage to be increasing as it crosses the Trigger Level, a negative Slope
requires the voltage to be decreasing.
Trigger Source The instrument input that supplies the signal to provide the trigger.
Transducer A device that receives energy from one system and retransmits (transfers) it, often in a
different form, to another system.
For example, t he cruise control transducer convert s a vehicle speed s ignal t o a
modulated vacuum output to control a servo.
Turbocharger A centrifugal device driven by exhaust gases that pressurize t he intake air, thereby
increasing the density of charge air and the consequent power output from a given
engine displacement.
USB Universal Serial Bus (visit www.usb.org for details.)
User’s Last Display The last display having been displayed just before the instrument was turned off.
Vertical Scale The scale used for vertical display (vertical sensitivity) expressed in certain unit s per
division.
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NTC A resist or t hat has a Negat ive Temperature Coeffic ient ; resistance decreases as
temperature increases.
O 2 Sensor Oxygen sensor
Off-time The part of an electrical signal during which an electrical device is de-energized.
On-time The part of an electrical signal during which an electrical device is energized.
OBD II On-Board Diagnostics Second Generation (or Generation Two)
OBD II Systems Provide comprehensive diagnostics and monitoring of emission controlling systems.
Open Loop An operating condition or mode based on programmed instructions and not modified by
a feedback system.
Peak Value The highest or lowest value of a waveform.
Peak-and-Hold A method f or regulat ing t he current flow through electronic fuel injectors. S upplies
higher current necessary to energize t he inject or, t hen drops t o a lower level just
enough to keep the injector energized.
Pixel The smallest graphic detail possible for the liquid crystal display (LCD)
Powertrain The elements of a vehicle by which motive power is generated and transmitted to the
driven axles.
Pressure (Absolute) The Pressure referenced to a perfect vacuum.
Pressure (Differential) The pressure difference between two regions, such as between the intake manifold and
the atmospheric pressures.
PTC A res istor that has a P ositive Temperat ure Coeff icient ; resistance increas es as
temperature increases.
Pulse A voltage signal that increases or decreases from a constant value, then returns to the
original value.
Pulse Modulated A circuit that maintains average voltage levels by pulsing the voltage on and off.
Rail A manifold for fuel injection fuel.
Range Specified limits in which measurements are done.
Reference Voltage An unaltered voltage applied to a circuit. Battery plus (B+) and ground (GND) are
examples of reference voltages.
Regulator (Voltage) A device that automatically controls the functional output of another device by adjusting
the voltage to meet a specified value.
Relay A generally electromechanical device in which connections in one circuit are opened or
closed by changes in another circuit.
Root Mean Square Conversion of AC voltages to the effective DC value.
(RMS)
RPM Engine speed expressed in Rotations Per Minute of the crankshaft.
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