natus Grass S88X Troubleshooting guide

Phone [phone] • Fax [phone] • Technical Support 877.472.7779 • E-mail [email protected]
Web site: www.natus.com Manual Part Number M643H05
Release D
S88X
Dual Output Square pulSe StimulatOr
Grass ®
USER &
SERVICE MANUAL

Publisher’s Notice
Natus Medical Incorporated
DBA Excel-Tech Ltd. (XLTEK)
2568 Bristol Circle
Oakville, ON L6H 5S1
Canada
phone: [phone]
fax: [phone]
toll-free: 1.877.472.7779 (USA only), 1.855.554.3184 (Canada only)
email: [email protected]
www.natus.com
EUROPEAN AUTHORIZED REPRESENTATIVE:
Natus Europe GmbH
Robert-Koch-Str. 1
82152 Planegg
Germany

© coPyright 2013 by excel-tech ltd. (xlteK)
The information in this publication is provided for reference only. All information
contained in this publication is believed to be correct and complete. Excel-Tech Ltd.
shall not be liable for errors contained herein nor for incidental or consequential
damages in connection with the furnishing, performance, or use of this material.
All product specifications, as well as the information contained in this publication,
are subject to change without notice.
This publication may contain or reference information and products protected by
copyrights or patents and does not convey any license under the patent rights of
Excel-Tech Ltd., nor the rights of others. Excel-Tech Ltd does not assume any liability
arising out of any infringements of patents or other rights of third parties.
All rights reserved. This document contains confidential or proprietary information
of Excel-Tech Ltd. No part of this document may be reproduced or transmitted in
any form or by any means without the written permission of Excel-Tech Ltd.
Excel-Tech Ltd. makes no warranty of any kind with regard to this material,
including but not limited to the implied warranties of merchantability and fitness
of a particular purpose.
trademarKs
AURA®, Comet-PLUS®, EC2®, FASS®, Grass®, Grass Technologies®, Neurotrac®,
Panorama®, SleepTrek®, SzAC®, TWin®, TWinLOOK® and TREA® are trademarks of
Natus Medical Incorporated.
Other brand and product names are trademarks or registered trademarks of their
representative holders.
Printed in the United States of America

imPortaNt
This manual is subject to periodic review, update, and revision. Customers are
cautioned to verify that the manual’s information applies to the software and
hardware present in the equipment.
This product performs as described in this manual, and in accompanying labels
and/or inserts, when assembled, operated, maintained, and repaired in accordance
with the instructions provided.
This product must be cleaned and checked periodically. Do not use a defective
product. Parts that are broken, missing, worn, or contaminated should be replaced
immediately. If repair or replacement becomes necessary, call or write to request
service advice from Grass.
This product must not be altered without the prior written approval of Grass. The
user of this product shall have the sole responsibility for any malfunction that
results from improper use, faulty maintenance, improper repair, unauthorized
service, or alteration by anyone other than Grass.
The safety, reliability, and performance of this device can only be assured under
the following conditions:
• If the device has been used according to the accompanying
operating instructions.
• If changes or repairs have been carried out by Grass.
• If it is used in buildings having ground equalization wiring that complies
with relevant UL, CSA, IEC or other local standards and regulations.
iNteNded use
The S88X Stimulator is a general purpose, electrical stimulator for nerve
and muscle that has a wide range of parameters to satisfy a wide range of
research applications.
FOR USE BY QUALIFIED PERSONS ONLY. NOT INTENDED FOR THERAPEUTIC
PURPOSES.

WarNiNgs
READ THIS BEFORE OPERATING S88X
The available voltage and current from this Stimulator may, under some
conditions, be sufficient to be lethal or cause burns, particularly with
high duration and/or high voltage settings.
It is the responsibility of the investigator/user, to determine for any given
application, the maximum safe levels of stimulation, and assure that such
stimulation levels will not be exceeded. In many applications, the mechanisms of
safe stimulation are not completely understood.
Parameters that affect safe stimulation levels are:
• Pulse Repetition Rate
• Pulse Duration
• Pulse Duty Cycle
• Voltage and/or Current Intensity
• Biphasic vs Monophasic Operation
• Total Time Exposure
• Electrode Impedance, Geometry, Area and Material
The S88X OUTPUT is NOT ISOLATED. Do not use on humans.
CONSULT GRASS IF YOU HAVE ANY CONCERNS ABOUT SAFE APPLICATION,
PARTICULARLY WHEN USED WITH OTHER EQUIPMENT.
NATUS MEDICAL INCORPORATED WAIVES THE RESPONSIBILITY
WHATSOEVER FOR ANY INJURIES INCURRED TO THE OPERATOR OF THIS
INSTRUMENT, OR TO ANY ANIMAL OR HUMAN SUBJECT AS A RESULT OF THE
IMPROPER USE AND/OR ABUSE OF THIS STIMULATOR.

S88X Dual Output Square Pulse Stimulator vii
Table of Contents
1. sPecificatioNs & symbols glossary ................................................. 1-11
SpecificationS......................................................................................1-11
GloSSaryofSymbolS..........................................................................1-12
2. iNtroductioN ................................................................................. 2-13
Safetyinformation.............................................................................2-13
   CAUTION...................................................................................2-13
   WARNING..................................................................................2-13
  electromaGneticcompatibilityinformation..........................................2-14
3. geNeral coNsideratioNs ................................................................. 3-15
  applicationS&capabilitieS..................................................................3-15
  accuracy&Waveform.......................................................................3-18
  linevoltaGerequirementS..................................................................3-19
Dutycycle........................................................................................3-19
  mountinG&inStallation....................................................................3-20
4. descriPtioN of circuits ................................................................... 4-21
General.............................................................................................4-21
  poWerSupply.....................................................................................4-21
  outputcircuit...................................................................................4-22
  S1&S2outputamplituDe.................................................................4-22

viii  Table of Contents
5. exPlaNatioN of coNtrols ................................................................ 5-25
  explanationofcontrolS.....................................................................5-25
  poWer...............................................................................................5-25
Setup&enter/accept.........................................................................5-25
  trainrate&Duration.......................................................................5-26
  S1/S2timinGparameterranGeS..........................................................5-26
TRAINRATe...................................................................................5-26
TRAINDURATION.............................................................................5-26
   S1/S2RATe...................................................................................5-26
   S1/S2DelAy.................................................................................5-26
   S1/S2DURATION............................................................................5-26
  S1&S2controlS..............................................................................5-27
FUNCTION......................................................................................5-27
   S1&S2PUlSeS.............................................................................5-27
SINGlePUlSeS................................................................................5-28
OUTPUTON/OFF............................................................................5-28
StimuluStiminGcontrolS....................................................................5-28
  outputamplituDe..............................................................................5-29
Syncout(SynchronouSoutputS)........................................................5-29
Syncin(SynchronouSinputS)..............................................................5-30
  monitorS...........................................................................................5-31
   S1/S2leDMONITORS....................................................................5-31
OUTPUTON/OFFleDMONITORS......................................................5-31
OUTPUTMONITOR..........................................................................5-31
  uSbinterface....................................................................................5-31
DutycyclelimitationS........................................................................5-32
6. comPuter coNtrol ......................................................................... 6-33
 computercontrol...................................................................................6-33
7. oPeratioN ..................................................................................... 7-35
 Setup.......................................................................................................7-35
Dutycyclelimit................................................................................7-35
  chooSeStimuluSiSolationunitS..........................................................7-36
  loaDSetup&SaveSetup.....................................................................7-37
SeTTINGUPTheS88XPARAMeTeRS....................................................7-37
SAvINGTheS88XSeTUP..................................................................7-37
   lOADINGASeTOFS88XSAveDPARAMeTeRS......................................7-37
  trainparameterSfunctionS................................................................7-38
   S1&S2TRAINDelAy....................................................................7-38
TRAINSyNClOCATION.....................................................................7-39
TyPeOFTRAINPARAMeTeRS..............................................................7-39

S88X Dual Output Square Pulse Stimulator ix
 baSicoperatinGmoDeS.............................................................................7-40
SinGlepulSeS.....................................................................................7-40
  repetitivepulSeS(S1orS2).................................................................7-41
SinGletrainS(S1orS2).....................................................................7-41
  repeatinGtrainS(rt)S1orS2...........................................................7-42
  S1SpecialmoDeS...............................................................................7-43
SyNCTOS1DelAy.........................................................................7-43
SyNCTOTRAINDURATION................................................................7-43
  S2SpecialmoDeS...............................................................................7-44
SyNCWIThS1(SS).........................................................................7-44
POSTS1TRAIN(PT).......................................................................7-45
SyNCTRAINTOS1(ST)...................................................................7-45
SINGleARRhyThMIC(SA)...............................................................7-46
SyNCTOS2DelAy.........................................................................7-47
TWINPUlSeMODe..........................................................................7-47
BIPhASICPUlSeMODe.....................................................................7-47
MONOPhASICPUlSeMODe...............................................................7-48
8. artifact, stimulus isolatioN & coNstaNt curreNt ............................. 8-49
StimuluSartifact...............................................................................8-49
SourceS&reDuctionofStimuluSartifactS..........................................8-50
StimuluSiSolation..............................................................................8-51
StimuluScurrentmonitorinG..............................................................8-53
9. troubleshootiNg & maiNteNaNce ..................................................... 9-55
General.............................................................................................9-55
  reSetcircuitry...................................................................................9-55
  troubleShootinGtipS..........................................................................9-55
  fielDSoftWareupGraDe......................................................................9-56
a. aPPeNdix ...................................................................................... a-57
  conStantvoltaGevS.conStantcurrentSourceS
  forpulSeStimulation........................................................................ a-57
b. aPPeNdix ...................................................................................... b-59
  S88xtiminGDiaGramS...................................................................... b-59

x  Table of Contents