580EXII Posibile Probleme

7/22/2019 580EXII Posibile Probleme

1/19

PreliminaryResearchReportonCanon580EXIIFlashFailuresByJimClark&TimAmbrose,ResearchandDevelopment

LPADesignBackground:SincethelaunchofitsPocketWizardMiniTT1andFlexTT5modelsinearly2009,LPADesign(A.K.A.

PocketWizard)hasbeenreceivingperiodiccallsandreportsfromcustomerswhoareusingtheirCanon

580EXIIflasheswiththePocketWizardControlTLradiosandexpressingconcernthatperhapstheirflash

mayhavebeendamagedbyusingaPocketWizardradiotriggerwithit.

Asofthetimeofthisreport(Jan,2011),thereareabout120140PocketWizardcustomerswhohave

reportedhavingoneormore580EXIIflashesdamagedwithcommonsymptomsoverthepast18+

months.

Ifthefailuremodewasrelatedtoourproduct,thiswouldworkouttolessthan0.5%ofour

MiniTT1/FlexTT5radio

units

which

were

connected

to

aflash

that

failed

and

less

than

1%

of

the

580EX

II

flashesthatwereconnectedweredamaged.

LPADesignhasconductedaseriousindepthinvestigationforseveralmonthsaswecontinuetocollect

dataandevidenceofthespecificsofthefailuremode. Inadditionwehavejuststartedtheoutside

researchassistanceofanalyticalchemistryprofessorGiuseppePetrucciattheUniversityofVermont.

Research:Thesymptomofthefailureisthatthe580EXIIwillnolongeroutputcontrolledamountsoflight. Itwill

onlyoutputfullpowerdumps. Thisfullpowerdumpwillhappenevenonapreflash,thereforeleaving

nostoredenergywithinthecapacitorleftforamainflashexposure.

ThetestingquicklyrevealedthatanIGBT(transistor)withintheflashisdamaged. Thispartismadeby

Renesas(part#RJP4301).

TheIGBTisusedtoturnofftheflowofcurrentthroughtheflashtubewhenthedesiredamountoflight

hasbeenreached. ThisIGBTisalsousedtocontrol(modulate)thebrightnessofthelightwheninHSS

(HighSpeedSync)withthehelpofafiberopticcablefeedingalightsensorwithinthemainbody.

AlthoughLPADesignhasbeenabletoidentifythesymptomoftheproblem,LPADesignhasnotbeen

abletotracethecauseoftheproblemtoourPocketWizardproductsandwehavenoknowledgeofthe

incidenceratesofthisproblemarisingindependentlywithoutPocketWizard,i.e.somenumberof580EX

IIflasheslikelyfailwithoutPocketWizardControlTLradiosinteractingwiththem.Wereceivedreports

ofthis

IGBT

failure

in

all

spectrums

of

use.

It

spans

multiple

different

Canon

camera

models,

below

XSyncandaboveinHSS(moreofteninHSS),TTLormanualmodesandonanyversionoffirmwarethat

thePocketWizardMiniTT1andFlexTT5havehadinpublicrelease. Evenbrandnewflashescouldfail.

Wehaveruledoutheatbuildupasacausesinceseveralhavefailedwithinthefirstdozenshotsafter

beingpulledoutofthecamerabag. Thisisallbasedonverbaldescriptionsfromcustomers.

ItalsohasfailedasmanytimeswithaPocketWizardAC5RFSoftShieldasithasfailedwithoutusingthe

AC5. SothereappearstobenochangeinoccurrencewhenusingtheAC5orAC7.


2/19

Wepurch

otherco

MostsigOnecom

replacem

Theseco

discharge

Repaired

periods

Soitbeca

Eventuall

andsoot

place.

Replacem

failwitho

Belowar

asedmanyo

moneleme

ificantobseontheme

ent.

dcommont

fromoneor

unitsthatha

henuseddir

mecleartha

wefoundt

builduparou

entofthefl

rwithouta

exampleso

fthefailedfl

tsbetween

vations:asthatALLf

hemewasth

moreendso

eonlytheI

ectlyonaCa

ttheIGBTw

attheflash

ndthe

ends

shheadssol

ocketWizard

the580EXII

ashesfrome

heunitstha

ailedflashu

atALLfailed

ftheflashtu

BTreplaced

oncamera

snttheonly

ead(tube/r

fthe

flash

tu

edthefailur

radio.

flashheads

ndusersso

failed.

itshavehad

unitshavevi

betotheme

willfrequen

ithoutaPo

failurecom

flector)was

be.Sparks

a

eproblems

hatwereca

ecouldtake

theIGBTda

iblesignsof

talreflector.

lyfailagain

ketWizardr

onentwithi

alsobadand

ndelectrical

ndtheflash

singIGBTfai

themapart

agedandn

electricalarc

ithinrelativ

dioinvolved

thesystem.

showedvisi

arcingwere

scouldnol

lurestorepe

ndstudyth

eded

ing/electric

elyshorttim

.

lesignsofa

pparentlyt

ngerbemad

at

l

sh

king

eto


3/19

Figure1:

oxidizatio

Figure2:

possible

Figure3:

housingi

Flashtubee

nofmetalre

Flashtubee

xidizationof

Inmoresev

nearthetu

dshowingb

flectornear

dwithtrigg

metalreflec

recasesthe

e.

lacksootbe

ubberends

rringshowi

ornearrubb

flashtubegl

indtubeon

al.

gblacksoot

erendseal.

ssischarred

rubbermoun

behindtube

inaringaro

t. Alsoshow

onrubberm

undwheret

spossible

ount. Alsos

emetalrefl

ows

ctor


4/19

Figure4:

Figure5:

Anotherexa

xampleofd

mpleofsoot

amagefrom

andelectrica

eflectortot

ldamageat

iggerringaf

ndofflasht

erelectrical

ube.

arcing


5/19

ElectricalWecaptu

Forrefer

theIGBT

Belowis

Figure6:

AnalysisofFredfailuree

nce,IGBTcu

mitterlead.

nexampleo

Inthemiddl

ailureModeentsaswell

rrentissens

fafailurewe

ofaHighSp

:asgoodwor

dbymeasur

havecaptur

eedSyncpul

ingunitsto

ingvoltagea

d

setrain,the

erifythepro

crossa0.01

IGBTfailsan

blemusinga

hm1%resis

shortsColle

noscilloscop

torinlinewi

ctortoEmitt

e.

th

er.


6/19

Figure7:

sparkjum

Closeupvie

pedtother

ofIGBTele

flectorandt

ctricalsignal

henintothe

. Notethat

collectoroft

theIGBTgat

heIGBT.

wasturnin offwhenth

e


7/19

MakingtInmanyc

frontedg

infeedba

Weare

s

thenegat

Figure8:

Note:To

eflashmorases(butno

eofthehous

cktothesen

eingthat

thi

iveflashtub

Shortcurren

traceisthe

pronetofaall)weares

ingorithas

sor.

sfiber

optic

cathodeov

tspikesonI

controllineg

ilure:eeingthatth

kink/pinch

ablecan

ma

rtothetrig

BTemitterc

oingtothet

efiberoptic

inthefiberl

ethe

flash

erringofth

ausedbyarci

iggercoildri

cablehaseit

inewhichmi

oresensitiv

tube.

ingtoreflect

vercircuit.

erpulledba

ghtbecausin

to

having

a

orortrigger

cksomefro

gsomeredu

sparkarc

fro

ing.

the

ction

m


8/19

Figure9:

Notethat

circuits.(

Intheory

fireatth

thatcaus

Tofurthe

withthet

aselimin

SameasFig

thearcpuls

appensafte

thisfigure9

momentth

dthearcing

rconfirmtha

riggerringa

tionofthec

re8(zoome

tothetrigg

rarcnotbef

showsthatt

tiscircleda

.

tthisisinfac

dsawasign

ircledpulseo

in)Shortcu

rringinthis

rewhichind

eflashesele

ove. Thisal

tarcingtoth

ificantreduc

nthedriver

rrentspikes

casepropag

icatesthatt

ctricalcontr

oindicatest

etriggerrin

ionincurren

ircuitline(t

nIGBTemit

atesbackwar

econtrolsi

lcircuitsdid

hatitsnota

,weplaced

tringingon

ptrace).

tercausedb

dsthrought

naldidnotc

notcauseth

CPUfirmwar

47Kohmre

hecircledev

arcing.

etriggercoi

usethearci

etriggercoil

edriveneve

sistorinseri

entaboveas

l

g.)

to

nt

s

well


9/19

Figure10

the580E

Notethat

Thisflash

: Typicaltrac

XIIonagoo

thecurrent

hasagoodp

eshowinga

workingfla

rofiledoes

ositioningof

reflash(wh

hthatdoes

othaveany

thefiberopt

ileusingaPo

otdamageI

spikesinthe

icandnosig

cketWizard

GBTs.

middleofth

sofkinksor

iniTT1/Fle

eIGBTONpe

bendsinthe

xTT5)totrig

riods.

fiber.

er


10/19

FlashTubAnothers

extendin

Onetheo

metalrefl

Manually

shortene

Wehave

Figure11

theflash

eAlignmentignificantob

intotherefl

ryisthatthis

ectorthe

sh

movingthef

didincreas

oundthatw

: NOTE:the

ube.

:servationist

ectoraremo

tubetrigger

rtestthereb

lashtubesh

therateat

ecannotget

ealedglassc

atflashesth

repronetof

ringposition

enabling

ar

wnonbotto

hicharcing

theIGBTtof

oversarere

athavethe

ailagain.

ing(topima

cingto

happ

mimagetot

ccurred. (H

ailifthefron

ovedfromt

lashtubeali

e)makesth

nmuch

easi

herightsuch

oweveritdid

tglasscover

heheadass

nedwithth

sparkgapdi

er.

thatthespa

notcauseth

isnotinplac

mbliesfore

triggerring

stancestoth

rkgapwas

eIGBTtofai

e.

sierviewing

e

l)

of


11/19

OzonefrOzoneis

(source

Inaseale

electrical

shorterdi

Ozoneca

generate

separate

HighSpe

discharge

Intheory

Thehead

thathold

LPADesi

damaget

Tofurthe

didcause

Sointhe

Withthes

(Model#

Pictureso

mUVandEleneratedby

ikipedia)

dcontainer(

breakdown

stances.

begenerat

inthepres

byaglasst

dSyncmod

inaheadth

thisgenerat

assemblyon

theflashtub

ntheorizedt

heIGBT.

rtestthisth

IGBTstofail.

rythebest

etheoriesin

106M)

The

fthetestset

ectricalfieldusingUVlig

suchasseale

oltageofair

dinthepre

nceofrapid

beishowco

(HSS)ofthe

thasamisal

shigherand

the580EXII

einplace. T

hatozonebu

ory,werem

Withthegl

aytohelpp

mind,LPAD

model106

upareonth

s:t,highvolta

dflashhead)

suchthatarc

enceofUVf

repeatedele

mmercial/i

580EXIIgen

ignedtubea

higherlevels

asaglassco

eozonehas

ildupinthe

vedtheglas

sscoverre

eventozone

signrented

readsOzon

followingp

es(1020KV

ozonecanb

ing(electrica

romflashtu

ctricaldischa

dustrialozo

eratesaloto

longwithim

ofozoneth

veroverthe

nowhereto

flashheadis

sfrontcover

oved,weca

buildupist

anOzoneGa

as

low

as

1

ge(Figs12,

)oranelectr

uilduptoda

ldischarge)

es. Howeve

rge. Pulsed

egenerator

frepeatingp

roperfeedb

tcantesca

frontandar

go.

causingthe

fromaflash

tgettheIG

ventilateth

sAnalyzerfr

ppb(10

par

13).

icspark(cor

ngerouslevel

anhappen

ritsfarmor

ighvoltage

swork.

ulsesofelec

ackfromthe

etheheada

ubberizedse

ailureevent

headassem

BTtofail.

eheadasse

mOzoneSo

sper

billion)

na).

sandreduce

ucheasiera

likelytobe

lectricalcha

tricalarc/

fiberopticc

ssembly.

alonbothen

thatultimat

lythattypic

bly.

lutions.

.

the

t

rge

ble.

ds

ely

lly


12/19

Figure12

Ozonega

Figure13

:This580EXI

scouldbesa

: OzoneSolu

Ihadthegla

mpledviath

tionsGasan

scoverrem

frontofthe

lyzermodel

vedfromth

housingthro

106M

einternalfla

ughtheplas

hheadasse

ticFresnelle

blysothat

s.


13/19

OzoneAOurfirstt

sealsthe

theflash

Weconfir

700mlpe

holeinth

Nextwe

theflash

(HSSmod

TheOzon

upofozo

readinga

Figure14

nalysisoftestwastoc

lashtubehe

iaanOCE3

medthat

Oz

rminute. In

efarbackof

ovedthe58

ofirespecifi

e). ACanon

eanalyzerh

nevs.time.

teraveragin

:

e580EXIIFnfirmweco

adassembly

cabletofire

onewas

star

ordertoena

theflashhea

0EXIIflasht

cally80pops

CPE4batter

savoltageo

heOzonea

gforeach10

lash:lddetectOz

insidethefla

t1secondi

ingto

be

de

leairtobe

dnearthepi

beoffthec

at1.5secon

packhadto

utputportth

alyzertakes

secondperi

one.Todot

shhead. We

tervalsfora

ected.The

rawnfromt

vot/hinge.

amerarunni

dintervalsat

beusedtoe

atwasconn

samplesofa

d.

isweremov

thensetthe

bout40seco

zoneanalyz

eflashhead

gviaitsow

maximump

nablefiring

ctedtoano

irevery10s

edtheglass

camerathat

nds.

ersamples

ai

,wehadto

opticaltrig

owerat1/80

hisfast.

scilloscopet

condsando

overplatet

wasconnec

rat

arate

of

rillatinyair

erinput. W

00thshutter

showtheb

tputsanew

at

edto

vent

set

peed

ild


14/19

Ascanbe

triggerin

isusedas

efficient

Shownb

Figure15

controls

possible

Sincethe

energyth

flashhea

Ourtheo

IIiswhat

Tofurthe

(seeFigur

seeninthe

hasamuch

thetrigger.

SStimingco

low(fig15)

: Showingfu

stem. Ther

henusingt

lightoutput

atwas

delive

washalfas

eticalconclu

causesmost

rconfirmthi

e16onfollo

copetraces

asterbuildu

Thislowerra

ntrolsystem

rethetwoli

llpowerHSS

dtracesho

ePocketWiz

henusingt

redby

the

fl

muchwhen

sionisthatt

oftheozone

,wealsofire

wingpage)

howninFig

ofOzonein

teofozone

usedbythe

htpulseout

lightoutput

stheshorte

ardFlexTT5

ePocketWi

shtube

was

singthePoc

erapidfirin

buildupand

dalongseri

re14,theC

sidetheflas

uildupislike

ocketWizar

putsasmeas

rom580EXII

firingtime

sthetriggeri

ardradiowa

thesame

bu

ketWizardFl

ofthe10KV

notthebrigh

sofnonHS

nonnatives

headthan

lyrelatedto

ControlTLs

uredbyaTh

whenfired

utbrighter

ingsystem.

sbrighterbu

tthe

resultin

exTT5.

triggercircu

tnessofthe

fullpowerli

ystemusing

henthePoc

themuchm

stem.

orLabsDET3

iaCanonsn

aximumout

thalfthedu

gozone

buil

itrepeatedly

lightoutput.

ghtpulsesfo

heirownop

ketWizardFl

reenergy

6Alightsens

ativeoptical

putthatis

ation,theto

upinside

th

insidethe5

rcompariso

ical

xTT5

or.

tal

0EX

.


15/19

Figure16

buildup

brightnes

Testmod

Canonsn

theIGBT

systemm

However

ringarou

lightemit

fullpowe

HSSpulse

Wearep

muchthe

triggerri

research

: Whenfirin

asnearlyzer

sofCanons

einFlexTT5

ativepulsed

ail.Wehad

ighthaveinc

thetestsdid

dtheflasht

tedbythefl

rnonHSSfla

has

only

asi

eparingtor

ozonewillc

gtotherefl

rinthefield

theflashusi

o. However

nativeoptica

irmware5.2

urationand

thoughtthat

reasedthec

nothavetha

ubewerelik

shsincealo

shpulseisfa

nglefiring

of

ntestsatth

angetheele

ctormetalh

ofozoneand

ngonlyafull

henwetrie

llytriggered

2(neverap

rightnessof

perhapsthe

ancesofaf

toutcome.

lythemore

gerduratio

brighteran

thetrigger

ri

University

ctricalbreak

ousing. Che

willbeassis

powerdum

dtoduplicat

SS(1/8000t

blicrelease)

theiroptical

brighterligh

ilureevent.

efoundtha

significantca

HSSpulseh

yetgenerat

ngon

the

fla

fVermont(

ownofairs

istryprofes

tingustofur

innonHSS

etheexactsh)theozone

wastotest

ETTLsystem

outputcapa

tthe10KVe

useoftheoz

asmanymor

esnearlyzer

shtube

at

th

VM)inthec

uchthatane

sorGiusepp

therourrese

(belowXSyn

amepulsed

uildupwas

urtheoryth

mightbeles

bilityofthe

lectricalpuls

oneformatio

efiringsoft

oozone. Thi

ebeginning

omingweek

lectricalspar

Petrucciof

archandthe

c)theozone

rationand

uchgreater

atduplicatin

pronetoha

ocketWizar

sfromthet

nandnotth

etriggerrin

sfullpower

fthe

light

o

tofindout

kwilljumpf

VMisa

ories.

.

g

ving

igger

eUV

. A

on

tput.

ow

om


16/19

PreflashBoost:PocketWizardintroducedbackinAprilof2009afirmwarefeaturethatenablesabrighterpreflashtobe

selectedbytheuser. Thedefaultwastohavethebrighterpreflashenabled.

InSeptemberof2010aspartofourongoingresearchintothisIGBTfailureproblemin580EXIIflashes,

wetried

atest

where

we

changed

the

default

of

the

preflash

to

be

disabled.

After5monthsofcollectingdatasincedefaultingtopreflashboostOFF,wehavefoundtherewasno

changeinreportedfailureratesince. Infact,thepreflashboostwasconfirmedtobedisabledinmostof

ourrecentreports.

OurcurrentconclusionsofaristhatthePreflashBoostfeatureisnotrelatedtothe580EXIIsIGBT

failure.

AnimportantthingtonoteisthatCanonspreflashisashortformofHSS. Itisjusta400uslongHSS

pulse.So

apreflash

can

generate

aquantity

of

the

high

voltage

pulses

similar

to

the

HSS

main

flash

mode. SoevenifauserisshootingatorbelowXSyncwithnonHSSexposures,thepreflashmaystill

begeneratingozone.

Furthertestswillbeneededtodetermineifpreflashesalonecouldgenerateenoughozonetocausethe

failureevenifwedisableanymainexposurelightoutput.

Othertesting:Weconductedmanyexperimentsaroundheat,static,andotherfactors.

UsinganESDgenerator,wedischarged11,00020,000voltsintomanyplacesona580EXIIbothalone

andmountedonaFlexTT5withandwithouttheAC5. Noissueswerenoted. The580EXIIandFlexTT5

arebothCEmarkedproductswhichmeanstheymustbeabletohandleacertainlevelofESDtoqualify

forsaleinEuropeancountries.

Heattestsoverlongperiods,torturetestsofhundredsoftriggersinvariousconfigurations,and

electricalshorttestsontheshoepinswereconducted.

NoneofthesetestsyieldedanyrepeatablefailuremodesorconclusivedataaroundIGBTfailure.


17/19

Asparto

designed.

people.

thefailur

occurred

TheCano

Figure17

reflector

theoretic

Therubb

theresearc

Thenewest

hilewehav

wasactuall

rightafterini

n430EXIIFl

:The

430EX

I

hanusedin

llyforextra

rendseal&

T

effortswea

430EXIIflas

ehadasingl

relatedtoa

tialpurchase

shHeadAss

Ihas

3times

the580EXII.

ventingand

mountused

he430EXIId

lsowantedt

fromCano

failurerepo

nIGBTorifi

,itmayhave

embly:

moreair

gap

Additionally

learancefro

onthe580E

esnotdam

reviewafe

isonethati

rt,theflash

hadanyrel

beenaman

spacebetwe

acutoutwa

melectrical

IIiselimina

geIGBTs.

otherflash

sworkingex

asnotsent

tiontoozon

ufacturingde

enthe

trigg

saddeddire

rcing.

edonthe4

esandlook

tremelywell

tousandwe

e. Sincethis

fect.

rring

wire

a

tlybelowth

0EXII.

thowthey

andreliable

couldnotco

onefailure

dthe

metal

flashtube

ere

or

nfirm


18/19

Figure18

flashuse

The430E

Ithas

bec

improve

models.

Theolder

thatthef

togetacc

opticalfe

problems

: The430EX

.

IIwasdesi

omeLPA

De

entofthed

Canon580Elashtubeish

identallyalig

edbacksens

.

IIdoesnotu

nedandstar

ignstheory

signonthes

flashdoes

eldinpositio

nedinthew

rinthe580E

easealede

tedshipping

hatdesign

p

eelementst

aveahead

ndirectlyby

ongposition

Xisverydiff

dcaptohol

beforePocke

roblemswith

preventfail

esignthatis

aprintedcir

byhandass

rentandma

theflashtu

tWizardCon

the

580EX

II

uresofasim

somewhatsi

uitboardan

mblyworke

ybelesssus

beinpositio

trolTLprodu

were

realize

ilarnatureo

milartothe

dhasnowa

rsatafactor

ceptibletoh

likethe580

tsexisted.

dand

neede

futureflash

80EXII,exc

fortheflash

. Also,the

ndassembl

EXII

d

pt

tube


19/19

Conclusions:(ThePerfectStorm)Itappearsthatsomecombinationofelementscomestogethertocreatetheriskandincreased

probabilityofanIGBTfailurewithinthe580EXII.

Sealedflashtubeassembly(internalzoomcarriageassembly) Misalignmentoftheflashtubewithinthereflectorsuchthatarcingismoreprobable Reducedopticalfeedbackviathefiberopticsensecableintheflashhead Dryerairwhereozonecanbegeneratedmoreeasily ElectricaldischargethroughthereflectoratamomentwhentheIGBTisturnedoff

Byreviewingheavilyused430EXIIflashes(Canonsnewest)andseeingnosignsatallofarcingwithinthe

reflectororontheflashtube,wehavetheorizedthatpossible580EXIIdesignissueswerecorrectedby

identifyingthesameproblemsdiscussedinthisdocumentandchangingthedesigntominimizethe

potentialfordamageonthenewer430EXIIflash.

PocketWizardmarketsandencouragespeopletogetoutandusehighspeedsync(HSS). Wemakeit

easierthaneverbeforeforlargernumbersofflashestobeusedinthesemodessinceoursystemdoes

nothavelimitationsinbrightsunlightconditionscomparedtoopticallytriggeredCanonflashes.

WebelievethatHSSflashmodeismorepronetohavefailurebutisnotarequirementoffailureto

happen. SomecombinationofTTLPreflashandorHSSmainflashseemstoberequired.

OurControlTLfirmwarecontrolsthebrightnessinfora580EXIIinHSSmodetonomorethanwhatis

permittedbytheCanon40D,50D,7DseriescameraswhichhavetheshortestHSSpulsedurations(when

flashisontopofthecamera)andthereforehavethehighestnativepermittedpowerrequestlevels.

Thesecamerashavetheshortestbladetraveltimesfortheirshutters.

OurPreflashboostmodedoesnotincreasethechancesofafailuresinceequalnumbersofpeoplehave

hadafailurewithitdisabledashavehaditenabled. OurAC5andAC7shieldingproductswerenoteven

usedinabout50%ofthereportedfailuresanddidnotevenexistwhenfirstreportsoffailuresstarted.

SowhilePocketWizardproductsdonotappeartocausethefailure,throughaggressivemarketingof

remoteHSSfeaturesofCanonsflasheswemaybeaccidentallycontributingtotherateinwhichfailures

happen.

Researchwillcontinueintryingtofindsolutions(ifany)toreducingtheriskoffailuresonthe580EXII.

Documents

580EXII Posibile Probleme