PowerLab 30 Series Owners Guide

This document was, as far as possible, accurate at the time of release. However, changes may have been made to the software and hardware it describes since then. ADInstruments Pty Ltd reserves the right to alter specifications as required. Late-breaking information may be supplied separately. Trademarks of ADInstruments PowerLab®, LabTutor® and MacLab® are registered trademarks of ADInstruments Pty Ltd. The names of specific recording units, such as PowerLab 8/30, are trademarks of ADInstruments Pty Ltd. Chart and Scope (application programs) are trademarks of ADInstruments Pty Ltd. Other Trademarks Apple, Mac and Macintosh are registered trademarks of Apple Computer, Inc. Windows, Windows 2000 and Windows XP are either registered trademarks or trademarks of Microsoft Corporation. All other trademarks are the property of their respective owners.

Product: ML866 PowerLab 4/30; ML870 PowerLab 8/30; ML880 PowerLab 16/30 Document Number: U-ML870/OG-002C Copyright © December 2006 ADInstruments Pty Ltd Unit 13, 22 Lexington Drive, Bella Vista, NSW 2153, Australia All rights reserved. No part of this document may be reproduced by any means without the prior written permission of ADInstruments Pty Ltd. Web: Technical Support: Documentation:

www.adinstruments.com [email protected] [email protected]

ADInstruments Pty Ltd ISO 9001:2000 Certified Quality Management System Reg. No. 1053

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PowerLab Owner’s Guide

Contents

Safety Notes

5

1 Overview

13

How to Use This Guide... 14 The PowerLab System... 14 First, Install the Software... 14 Next, Check Your PowerLab... 15 Other ADInstruments Hardware... 15 The PowerLab... 16 The Front Panel... 16 The Back Panel... 19

2 Setting Up

23

The PowerLab Self-test... 24 Connecting the PowerLab... 25

A Technical Aspects

27

How Does it Work?... 28 The Analog Inputs... 29 PowerLab Accuracy... 30 The External Trigger... 30 The Analog Outputs... 32 Connections... 32 Pod Connectors... 32 USB Port... 33 I2C Expansion Port... 33 Digital Input and Output Ports... 34 Serial Port... 35 USB Connections... 35 USB Connection Rules... 36

Contents

B Specifications

39

Glossary

43

Index

51 iii

Safety Notes

Statement of Intended Use All products manufactured by ADInstruments are intended for use in teaching and research applications and environments only. ADInstruments products are NOT intended to be used as medical devices or in medical environments. That is, no product supplied by ADInstruments is intended to be used to diagnose, treat or monitor a subject. Furthermore no product is intended for the prevention, curing or alleviation of disease, injury or handicap. Where a product meets IEC 60601-1 it is under the principle that: • •

it is a more rigorous standard than other standards that could be chosen, and it provides a high safety level for subjects and operators.

The choice to meet IEC 60601-1 is in no way to be interpreted to mean that a product: • • •

Safety Notes

is a medical device, may be interpreted as a medical device, or is safe to be used as a medical device.

5

Safety Symbols Devices manufactured by ADInstruments that are designed for direct connection to humans are tested to IEC 601-1:1998 (including amendments 1 and 2) and 60601-1-2, and carry one or more of the safety symbols below. These symbols appear next to those inputs and output connectors that can be directly connected to human subjects.

! BF symbol: Bodyprotected equipment

CF symbol: Cardiacprotected equipment

Warning symbol: ‘see documentation’

The three symbols are: •

•

•

BF (body protected) symbol. This means that the input connectors are suitable for connection to humans provided there is no direct electrical connection to the heart. CF (cardiac protected) symbol. This means that the input connectors are suitable for connection to human subjects even when there is direct electrical connection to the heart. Warning symbol. The exclamation mark inside a triangle means that the supplied documentation must be consulted for operating, cautionary or safety information before using the device.

Further information is available on request.

Bio Amp Safety Instructions The Bio Amp inputs displaying any of the safety symbols are electrically isolated from the mains supply in order to prevent current flow that may otherwise result in injury to the subject. Several points must be observed for safe operation of the Bio Amp:

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PowerLab Owner’s Guide

•

•

•

All Bio Amp front-ends (except for the ML138 Octal Bio Amp) and PowerLab units with a built-in Bio Amp are supplied with a 3-lead or 5-lead Bio Amp subject cable and lead wire system. The ML138 Octal Bio Amp is supplied with unshielded lead wires (1.8 m). Bio Amps are only safe for human connection if used with the supplied subject cable and lead wires. All Bio Amp front-ends and PowerLab units with a built-in Bio Amp are not defibrillator-protected. Using the Bio Amp to record signals during defibrillator discharges may damage the input stages of the amplifiers. This may result in a safety hazard. Never use damaged Bio Amp cables or leads. Damaged cables and leads must always be replaced before any connection to humans is made.

Isolated Stimulator Safety Instructions The Isolated Stimulator outputs of a front-end signal conditioner or PowerLab with a built-in isolated stimulator are electrically isolated. However, they can produce pulses of up to 100 V at up to 20 mA. Injury can still occur from careless use of these devices. Several points must be observed for safe operation of the Isolated Stimulator: • • • • •

•

• •

Safety Notes

The Isolated Stimulator output must only be used with the supplied bar stimulus electrode. The Isolated Stimulator output must not be used with individual (physically separate) stimulating electrodes. Stimulation must not be applied across the chest or head. Do not hold one electrode in each hand. Always use a suitable electrode cream or gel and proper skin preparation to ensure a low-impedance electrode contact. Using electrodes without electrode cream can result in burns to the skin or discomfort for the subject. Subjects with implantable or external cardiac pacemakers, a cardiac condition, or a history of epileptic episodes must not be subject to electrical stimulation. Always commence stimulation at the lowest current setting and slowly increase the current. Stop stimulation if the subject experiences pain or discomfort.

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•

Do not use faulty cables, or those that have exhibited intermittent faults.

•

Do not attempt to measure or record the Isolated Stimulator waveform while connected to a subject using a PowerLab input or any other piece of equipment that does not carry the appropriate safety symbol (see Safety Symbols above).

Always check the status indicator on the front panel. It will always flash green each time the stimulator delivers a current pulse. A yellow flash indicates an ‘out-of-compliance’ (OOC) condition that may be due to the electrode contact drying up. Always ensure that there is good electrode contact at all times. Electrodes that are left on a subject for some time need to be checked for dry contacts. An electrode impedance meter can be used for this task. •

•

Always be alert for any adverse physiological effects in the subject. At the first sign of a problem, stimulation must be stopped, either from the software or by flicking down the safety switch on the front panel of any built-in Isolated Stimulator or the ML180 Stimulus Isolator. The ML180 Stimulus Isolator is supplied with a special transformer plug pack. The plug pack complies with medical safety requirements. Therefore, under no circumstances should any other transformer be used with the Stimulus Isolator. For a replacement transformer plug pack please contact your nearest ADInstruments representative.

General Safety Instructions To achieve the optimal degree of subject and operator safety, consideration should be given to the following guidelines when setting up a PowerLab system either as stand-alone equipment or when using PowerLab equipment in conjunction with other equipment. Failure to do so may compromise the inherent safety measures designed into PowerLab equipment. The following guidelines are based on principles outlined in the international safety standard IEC60601-1-1: General requirements for safety - Collateral standard: Safety requirements for medical systems. Reference to this standard is required when setting up a system for human connection.

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PowerLab Owner’s Guide

PowerLab systems (and many other devices) require the connection of a personal computer for operation. This personal computer should be certified as complying with IEC60950 and should be located outside a 1.8 m radius from the subject (so that the subject cannot touch it while connected to the system). Within this 1.8 m radius, only equipment complying with IEC60601-1 should be present. Connecting a system in this way obviates the provision of additional safety measures and the measurement of leakage currents. Accompanying documents for each piece of equipment in the system should be thoroughly examined prior to connection of the system. While it is not possible to cover all arrangements of equipment in a system, some general guidelines for safe use of the equipment are presented below: • •

• • •

•

•

•

•

Safety Notes

Any electrical equipment which is located within the SUBJECT AREA should be approved to IEC60601-1. Only connect those parts of equipment that are marked as an APPLIED PART to the subject. APPLIED PARTS may be recognized by the BF or CF symbols which appear in the Safety Symbols section of these Safety Notes. Only CF-rated APPLIED PARTS must be used for direct cardiac connection. Never connect parts which are marked as an APPLIED PART to those which are not marked as APPLIED PARTS. Do not touch the subject to which the PowerLab (or its peripherals) is connected at the same time as making contact with parts of the PowerLab (or its peripherals) that are not intended for contact to the subject. Cleaning and sterilization of equipment should be performed in accordance with manufacturer’s instructions. The isolation barrier may be compromised if manufacturer’s cleaning instructions are not followed. The ambient environment (such as the temperature and relative humidity) of the system should be kept within the manufacturer’s specified range or the isolation barrier may be compromised. The entry of liquids into equipment may also compromise the isolation barrier. If spillage occurs, the manufacturer of the affected equipment should be contacted before using the equipment. Many electrical systems (particularly those in metal enclosures) 9

•

depend upon the presence of a protective earth for electrical safety. This is generally provided from the power outlet through a power cord, but may also be supplied as a dedicated safety earth conductor. Power cords should never be modified so as to remove the earth connection. The integrity of the protective earth connection between each piece of equipment and the protective earth should be verified regularly by qualified personnel. Avoid using multiple portable socket-outlets (such as power boards) where possible as they provide an inherently less safe environment with respect to electrical hazards. Individual connection of each piece of equipment to fixed mains socketoutlets is the preferred means of connection.

If multiple portable socket outlets are used, they are subject to the following constraints: • • •

They shall not be placed on the floor. Additional multiple portable socket outlets or extension cords shall not be connected to the system. They shall only be used for supplying power to equipment which is intended to form part of the system.

Cleaning and Sterilization ADInstruments products may be wiped down with a lint free cloth moistened with industrial methylated spirit. Refer to the Data Card supplied with transducers and accessories for specific cleaning and sterilizing instructions.

Preventative Inspection and Maintenance PowerLab systems and ADInstruments front-ends are all maintenance-free and do not require periodic calibration or adjustment to ensure safe operation. Internal diagnostic software performs system checks during power up and will report errors if a significant problem is found. There is no need to open the instrument for inspection or maintenance, and doing so within the warranty period will void the warranty.

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PowerLab Owner’s Guide

Your PowerLab system can be periodically checked for basic safety by using an appropriate safety testing device. Tests such as earth leakage, earth bond, insulation resistance, subject leakage and auxiliary currents and power cable integrity can all be performed on the PowerLab system without having to remove the covers. Follow the instructions for the testing device if performing such tests. If the PowerLab system is found not to comply with such testing you should contact your PowerLab representative to arrange for the equipment to be checked and serviced. Do not attempt to service the device yourself.

Environment Electronic components are susceptible to corrosive substances and atmospheres, and must be kept away from laboratory chemicals. Storage Conditions

• •

Temperature 0–40 °C Non-condensing humidity in the range 0–95%.

Operating Conditions

• •

Temperature 0–35 °C Non-condensing humidity 0–90%.

Disposal

•

Safety Notes

Forward to recycling center or return to manufacturer.

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PowerLab Owner’s Guide

Overview

1

Your PowerLab® recording unit, together with a range of specialized application programs, provides a versatile data recording and analysis system when used with a Windows or Macintosh computer. This chapter provides an overview of the PowerLab system and describes the basic features, connectors and indicators of the /30 series PowerLabs.

Note that the software on the Software Installer CD should be installed before you connect the PowerLab to your computer.

Chapter 1 Overview

13

How to Use This Guide This owner’s guide describes how to set up and begin using your PowerLab recording unit. The chapters provide an overview of the PowerLab system (the combined software and hardware package), and a more detailed look at the features of your recording unit and its connection to your computer. The appendices provide technical information about the recording unit and solutions to problems. At the end of this guide is a glossary of hardware terms and an index. The specifications and diagrams included in the appendices are there to help the more technically minded to understand what the PowerLab can and cannot do, but this is not a service manual: only an authorized ADInstruments representative should attempt repairs. If you modify the recording unit yourself, you void any rights you have under warranty. The user’s guides for the Chart and Scope application programs provide detailed information about using the software of the PowerLab system for acquiring, storing and analyzing data. Read them after you have connected the PowerLab to your computer.

The PowerLab System The PowerLab system is an integrated system of hardware and software designed to record, display and analyze experimental data. The hardware includes the PowerLab recording unit and various ancillary devices (front-ends, pods and so on); the software consists of the Chart and Scope application programs, and supplementary modules and extensions, which run on the computer to which the PowerLab is connected. Your /30 PowerLab has considerable computing power of its own and performs many tasks during data recording. Once the PowerLab transfers data to the computer, they are available for display, manipulation, printing, storage and retrieval. The PowerLab 4/30 has four inputs for recording external signals, the 8/30 has eight and the 16/30 has sixteen.

First, Install the Software Two main application programs and their documentation are provided with each PowerLab. The Chart application emulates a 14

PowerLab Owner’s Guide

multi-channel chart recorder (of up to 16 channels, depending on the PowerLab model). Scope emulates a two-channel storage oscilloscope. Both provide many other powerful features in addition, including channel calculations, triggering options, software-controlled stimulus generation and automated recording and analysis. Their user’s guides describe them in full; the Getting Started with PowerLab manual provides summaries. You must install the software to use your PowerLab. Full installation instructions are included in the Getting Started with PowerLab manual.

Next, Check Your PowerLab Please do not attempt to connect the PowerLab to a power outlet or computer or turn it on until you have read the first two chapters of this guide, and have checked it as described below. 1. Check that all items in the accompanying packing list are included in the box. 2. Check that there are no obvious signs of external damage to the PowerLab. 3. Check that there are no obvious signs of internal damage, such as rattling. Pick up the PowerLab, tilt it gently from side to side, and listen for anything that appears to be loose. If anything is missing, or the PowerLab seems to be damaged in any way, contact your authorized ADInstruments representative immediately and describe the problem. Arrangements can be made to replace or repair the PowerLab. Up-to-date contact addresses are available in the software and from the ADInstruments website.

Other ADInstruments Hardware ADInstruments has a range of optional ancillary devices that can be connected to the PowerLab to extend the system’s capabilities. They afford extra signal conditioning and other features, and extend the types of experiments you can conduct and the data you can record. Front-ends are advanced signal conditioners (the Bio Amp front-end, for instance, lets you perform electrically isolated measurements of biological signals). They are automatically recognized by the PowerLab system and integrated into its programs, operating under

Chapter 1 Overview

15

full software control. Pods are basic signal conditioners, more limited (but cheaper) than front-ends. Various transducers can plug into a PowerLab, front-end or pod, depending on their type. A PowerLab can usually have as many front-ends, pods, stand-alone instruments or transducers connected to it as it has appropriate connectors. All are easily added to or transferred among PowerLabs. Full information on such hardware is available from your local ADInstruments representative or from the ADInstruments website.

The PowerLab It is a good idea to get familiar with some of the external features of your PowerLab before connecting it to a power source. The rest of this chapter discusses the different features, connectors and indicators of the /30 series PowerLabs.

The Front Panel The front panel of your PowerLab provides most of the connectors for obtaining external signals, and indicators for various functions. This section describes each of the front panel features. The PowerLab 4/30 has three indicators at the left of the front panel, one BNC connector for the external trigger, two BNC connectors for output and four BNC connectors (marked Input 1 - 4) with four alternative pod (DIN) connectors for Inputs 1 - 4, for recording external signals.

Figure 1–1 The front panel of the PowerLab 4/30

Pod (DIN) connectors

Trigger Power and Status Indicators

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Analog output connectors

Analog input connectors

PowerLab Owner’s Guide

The PowerLab 8/30 has three indicators at the left of the front panel, one BNC connector for the external trigger, two BNC connectors for output and eight BNC connectors (marked Input 1 - 8) with four alternative pod (DIN) connectors for Inputs 1 - 4, for recording external signals. Figure 1–2 The front panel of the PowerLab 8/30

Pod (DIN) connectors Power and Trigger Status Indicators Analog input connectors Analog output connectors

The PowerLab 16/30 has three indicators at the left of the front panel, one BNC connector for the external trigger, two BNC connectors for output and sixteen BNC connectors (marked Input 1 - 16) with four alternative pod (DIN) connectors for Inputs 1 - 4, for recording external signals. Figure 1–3 The front panel of the PowerLab 16/30

Pod (DIN) connectors Power and Trigger Status Indicators Analog output connectors

Analog input connectors

Indicators

All three labeled indicators on the front panel should turn on at least briefly while the PowerLab is started up. In normal circumstances, the Power indicator should glow blue and then stay lit, the Status indicator should flash yellow and then stay green and the Trigger indicator should flash yellow and then turn off. The Power indicator is

Chapter 1 Overview

17

a blue light, which simply shows that the PowerLab is getting power. When an external trigger signal is received, the Trigger indicator will glow yellow. The Status indicator provides some visual indication of what the PowerLab is doing, and will flash different patterns and colors depending on the state of the PowerLab. Table 1–1 Status indicator states

Status Indicator Off

Meaning Idle and not yet initialized by the software.

Green

Idle, initialized, and waiting for a command from the computer.

Yellow

Sampling, or communicating with the computer.

Four red flashes then one yellow

The PowerLab has detected a low-level software or hardware fault. It will repeat until the PowerLab is turned off.

Red flashes

The PowerLab has detected an internal fault during the power-up test. It will repeat until the PowerLab is turned off.

Analog Inputs

The analog inputs used to record external signals can handle signals from ±10 V down to the microvolt (μV) range without the need for additional external amplification. Each PowerLab analog input has an independently programmable gain amplifier with its own filtering, and AC/DC coupling. You can set up each input independently to suit your requirements using the software. Note that applying more than ±15 V to the analog inputs can damage the circuitry. ▲WARNING PowerLab inputs and outputs are not electrically isolated (except for the Bio Amp input and Isolated Stimulator outputs on some PowerLabs and frontends). Human subjects must not be connected to the PowerLab outputs and inputs either directly or with uninsulated transducers. If such measurements are to be made, an electrically isolated ADInstruments front-end, insulated transducer or other approved electrically isolated device must be used 18

The PowerLab 4/30 has four independent analog inputs (marked Input 1-4) all of which have alternative connectors. The PowerLab 8/30 has eight independent analog inputs (marked Input 1 - 8), the first four of which have alternative connectors. The PowerLab 16/30 has sixteen independent analog inputs (marked Input 1 -16), the first four of which have alternative connectors. In either case, the BNC connectors for Inputs 1 - 4 can be used for single-ended input, and the 8-pin DIN pod connectors can be used for either single-ended or differential input. Single-ended inputs record the difference between signal and ground, whereas differential inputs record the difference between positive and negative input signals. Do not attempt to record from both the BNC and pod connectors for any one input at the same time, or the signals will compete.

PowerLab Owner’s Guide

Pod connectors allow the connection of ADInstruments pods - small, low-cost units for specific tasks, for use with precalibrated transducers. Unless they are so labeled, transducers should not be connected directly to pod connectors on the PowerLabs (unsuitable transducers will give a very weak signal). Transducers designed for direct connection can be provided with power and control, since the pod connectors also provide some of the functions of the I2C output. Analog Output

The PowerLab can generate a stimulus voltage through its analog output sockets (marked Output 1 and Output 2), giving positive, negative, differential, or independent stimuli, depending on the sockets used and the software settings. By default, the outputs are used for complementary (differential) stimulation, where Output 1 is positive and Output 2 is negative. When Output 1 is used, a positive stimulus voltage (set up in the software) gives a positive voltage output, and a negative voltage a negative one. When Output 2 is used, the voltage outputs are inverted. When both output sockets are used, the stimulus is the difference between the voltages at the positive and negative outputs: you could generate up to a 20-volt pulse, using a setting of ±10 V. Trigger

The external trigger connector allows you to use an external signal to synchronize recording to an external event. This input can handle voltages of up to ±12 V. The threshold voltage (the voltage above which the trigger circuit activates) is 1.5 volts for a rising edge. When the trigger threshold is crossed, the indicator beside the external trigger connector will glow yellow. The external trigger is described in more detail in Appendix A, and the software documentation covers its practical use in normal recording.

The Back Panel The PowerLab back panel provides the ports to connect the PowerLab to the computer, front-ends, the power outlet and so on. This section describes each of the back panel features. The back panel is the same for all the /30 series PowerLabs.

Chapter 1 Overview

19

Figure 1–4 The back panel of the PowerLab 4/30, 8/30 and16/30

Cooling fan

I2C Output connector USB connector

Power switch

Digital Output connector

Ground

Digital Input connector

Device rating information Power socket

Serial connector

I2C Output Port

The I2C output port provides power and communications for frontends manufactured by ADInstruments. As many front-ends as there are analog inputs can be daisy-chained together and connected to the I2C port. Only 50 mA maximum current can be provided through this bus, so it should not be used for third-party devices drawing more current. USB Port

The PowerLab connects to your computer using a USB port. This requires computers with USB connectors or a PCI USB card. You can safely turn on or off, or disconnect or reconnect, a USBconnected PowerLab while the computer remains on, in most cases. The application program (Chart or Scope) must not be running while you do this, though. Read the details on USB in Appendix A of this guide before connecting your PowerLab to your computer using USB. Digital Input and Output Ports

The digital input and output ports let you monitor and control external devices, respectively, with the PowerLab.

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PowerLab Owner’s Guide

The digital input monitors state changes: you can have a predefined comment automatically inserted during recording when a digital input changes to a particular state. The eight lines of the connector allow monitoring of up to eight devices. The digital output can turn on and off external devices, for example pumps, relays, and indicator lights, or can signal to some other device. The eight lines of the connector allow control of up to eight devices. Technical details of the Digital Input and Output connectors are given in Appendix A. More information on the use of digital inputs and outputs is given in the user’s guide for the software. Serial Port

The PowerLab is fitted with an RS-485 serial communication port. It is not currently in use, but is meant for connection in the future to specialized devices controlled from the PowerLab system. Ground Connection

A special earthing (grounding) stud has been provided on the rear of the PowerLab. This is an equipotential bonding connection post compatible with the DIN 42801 standard. If the ground connector post is used, the power cord ground connection should not be used: a power cord with no ground connection should be used instead. The ground connector post on the rear panel is used as a primary earth connection (equipotential connection point) in situations that require this type of connection, or if there is no ground provided via the power cord. Safety standards in laboratories and similar environments may require additional grounding protection when connecting equipment to human subjects. In such cases, an equipotential connection may be used for all linked equipment to prevent ground loops, and power cords with no ground connections should be used. Power Connections

The power switch on the back right of the PowerLab turns the PowerLab on and off; the 3-pin IEC power socket is used to connect your PowerLab to a 3-pin earthed (grounded) power cable. The power supply is universal, and can use all common international mains power supplies (auto-switching, 90–250 V AC, 50/60 Hz).

Chapter 1 Overview

21