Measurement Computing WavePort rev.3.0 User Manual
Waveport, User's manual, High-speed portable data acquisition systems
© 2000 by IOtech, Inc.
September 2000
Printed in the United States of America
WavePort
User's Manual
High-Speed Portable Data Acquisition Systems
the smart approach to instrumentation ™
IOtech, Inc.
25971 Cannon Road
Cleveland, OH 44146-1833
Phone: (440) 439-4091
Fax: (440) 439-4093
E-mail (Product Information):
Internet:
WavePort
User's Manual
High-Speed Portable Data Acquisition Systems
p/n
1036-0901
Rev.
3.0
Table of contents
Document Outline
- WavePort User's Manual
- Warranty Information
- Manual Layout
- Table of Contents
- Chapter 1 - unpacking and Inspecting your WavePort Package
- Chapter 2 - An Introduction to WavePorts
- Chapter 3 - System Setup
- Chapter 4 - Hardware and Operation Reference
- Chapter 5 - Software, An Introduction
- Chapter 6 - WaveView
- Chapter 7 - DIAdem®
- Chapter 8 - Troubleshooting
- Chapter 9 - Maintenance, Service, and Part Replacement
- Chapter 10 - WavePort/PE and WavePort/V Specifications
- WavePort/PE Specifications
- WavePort/V Specifications
- This section provides Analog Specifications Applicable to:
- WavePort/V8 - WaveBook (8 channels total)
- WavePort/V16 - WaveBook with one expansion module (16 channels total)
- WavePort/V24 - WaveBook with two expansion modules (24 channels total)
- PGA Filter
- Triggering
- Pulse Trigger
- Included Accessories and Software
- Included Accessories and Software
- Appendix A – Using Accelerometers
- Appendix B – WBK20A PCMCIA Option, Setup Notes
- Glossary
- Acquisition
- A collection of scans acquired at a specified rate as controlled by the sequencer.
- Analog signal
- A signal of varying voltage or current, resistance, temperature such as the output of a sensor.
- Analog-to-Digital Converter (ADC)
- A circuit or device that converts analog signals into digital values, such as binary bits, for use in digital computer processing.
- API
- Application Program Interface. The interface program within the WaveView system’s driver that includes function calls specific to WavePort hardware and can be used with user-written programs (several languages supported).
- Bipolar
- A range of analog signals with positive and negative values (e.g., -5 to +5 V); see unipolar.
- Buffer
- Buffer refers to a circuit or device that allows a signal to pass through it, while providing isolation, or another function, without materially altering the signal. Buffer usually refers to:
- A device or circuit that allows for the temporary storage of data during data transfers. Such storage can compensate for differences in data flow rates. In a FIFO (First In - First Out) buffer, the data that is stored first is also the first data to le
- A follower stage used to drive a number of gates without overloading the preceding stage.
- An amplifier which accepts high source impedance input and results in low source impedance output (effectively, an impedance buffer).
- Buffer Amplifier (see Buffer Amplifier).
- Buffer Amplifier
- An amplifier used primarily to match two different impedance points, and isolate one stage from a succeeding stage in order to prevent an undesirable interaction between the two stages. (Also see, Buffer).
- Channel
- In reference to WavePort, channel simply refers to a single input, or output entity.
- In a broader sense, an input channel is a signal path between the transducer at the point of measurement and the data acquisition system. A channel can go through various stages (buffers, multiplexers, or signal conditioning amplifiers and filters). In
- An output channel from a device can be digital or analog. Outputs can vary in a programmed way in response to an input channel signal.
- Common mode
- Common mode pertains to signals that are identical in amplitude and duration; also can be used in reference to signal components.
- Common mode voltage
- Common mode voltage refers to a voltage magnitude (referenced to a common point) that is shared by 2 or more signals. Example: referenced to common, Signal 1 is +5 VDC and Signal 2 is +6 VDC. The common mode voltage for the two signals is +5.5 VDC [(5
- Crosstalk
- An undesired transfer of signals between system components or channels. Crosstalk often causes signal interference, more commonly referred to as noise.
- Digital-to-Analog Converter (DAC)
- A circuit or device that converts digital values (binary bits), into analog signals.
- Differential mode
- The differential mode measures a voltage between 2 signal lines for a single channel. (Also see single-ended mode).
- Differential mode voltage
- Differential mode voltage refers to a voltage difference between two signals that are referenced to a common point.
- Example: Signal 1 is +5 VDC referenced to common. Signal 2 is: +6 VDC referenced to common.
- If the +5 VDC signal is used as the reference, the differential mode voltage is: +1 VDC (+ 6 VDC - +5 VDC = +1VDC).
- If the +6 VDC signal is used as the reference, the differential mode voltage is:
- -1 VDC (+ 5 VDC - +6 VDC = -1 VDC).
- ESD
- Electrostatic discharge (ESD) is the transfer of an electrostatic charge between bodies having different electrostatic potentials. This transfer occurs during direct contact of the bodies, or when induced by an electrostatic field. ESD energy can damage
- Excitation
- Some transducers [e.g. strain gages, thermistors, and resistance temperature detectors (RTDs)] require a known voltage or current input in order for the sensor to operate. This known input is called the Excitation.
- Gain
- The degree to which a signal is amplified (or attenuated) to allow greater accuracy and resolution; can be expressed as ×n or ±dB.
- Isolation
- The arrangement or operation of a circuit so that signals from another circuit or device do not affect the isolated circuit. In reference to WavePort, isolation usually refers to a separation of the direct link between the signal source and the analog-t
- Linearization
- Some transducers produce a voltage in linear proportion to the condition measured. Other transducers (e.g., thermocouples) have a nonlinear response. To convert nonlinear signals into accurate readings requires software to calibrate several points in t
- Multiplexer (MUX)
- A device that selects a signal from among several signals and outputs it on a single channel.
- Sample (reading)
- The value of a signal observed on a channel at an instant in time. When triggered, the ADC reads the channel and converts the sampled value into a digital representation.
- Scan
- A series of measurements across a pre-selected sequence of channels.
- Sequencer
- Defines and controls the state of the measurement system for each step of a scan.
- Simultaneous Sample-and-Hold
- An operation that captures samples from multiple channels at the same instant in time. The result is elimination of time skew between measurement of individual channels.
- Single-ended mode
- Measurement of a voltage between a signal line and some reference that may be shared with other channels.(Also see differential mode).
- Trigger
- An event to start a scan or mark an instant during an acquisition. A trigger can be a TTL signal, a specified signal level, a button manually or mechanically engaged, or a software command.
- TTL
- Transistor-Transistor Logic (TTL) typically used to communicate logic signals where a logical 0 is defined by a voltage level of <0.8V and logical 1 is defined as 2.4-5V.
- Unipolar
- A range of analog signals between zero and some positive value (e.g., 0 to 10 V).