No. 51947
V-32D50
V-32D30
V-32D20
3
SAFETY PRECAUTIONS
1. The d esign of t hi s p ro du ct c ont ains spec i al h ar dware, m an y
ci rcu it s a nd co mp on ent s s pecially for saf ety purp oses. F or
continued protection, no changes should be made to the
or igi na l des ig n u nless a uth or ized in wr iti ng by t he m an uf actu re r.
Rep lacem en t par ts m ust be id ent ic al t o t hos e u sed in th e
or igi na l cir cuit s. S er vic e sho ul d be per f or me d b y qu al ifi ed
p ers onn el o nl y.
2. Al te r ation s of th e desig n o r ci rcu i tr y of th e p r odu cts s hou l d n ot
b e mad e. A ny de si gn alte ra ti ons o r ad diti o ns will vo id th e
manufacturer's warranty and will further relieve the
m anu fact ur er of resp ons ib ilit y f or pe rs ona l in ju ry or p rope rt y
d am age r esu lt in g t her ef r om.
3. M an y e l ectr ical an d m ech an ic al pa rt s in th e p r odu cts h ave
sp ecial saf ety-relat ed c har act eris tics. Th ese charac ter istics are
oft en n ot e vid en t fr om visu al in spe cti on no r can t he pr ote ction
aff or de d by th em n ecess aril y be o bta in ed b y usi ng
r eplac ement co mp on ent s ra ted for h ig her vo l tag e, wa ttag e, etc.
Rep lacem en t pa rt s wh ic h h ave t hes e sp eci al s afet y
ch ar acter isti cs a re i d enti fie d in th e par ts list of S ervi ce m an ua l.
Electrical components having such features are identified
by shading on the schematics and by (!
!!
!) on the parts list
in S ervice manual . Th e u se of a su bst itu te re plac em en t w hich
does not have the same saf ety characterist ics as the
r eco mm en de d re plac em en t pa rt sho wn i n the pa rts list of
Se rvice ma nu al m ay c aus e sh ock, f ir e, or o th er haz ar ds.
4. Use isola tion tr ansf orme r wh en hot c hass is .
The chassis and any sub-chassis contained in s ome products
ar e c on nect ed to on e si de of th e AC p ow er line . An isola tion
tr ansf or mer of ad equ ate cap acity sh ou ld be i nser t ed bet we en
th e p r odu ct and t he AC p ower su pp ly p oi nt while p er for ming
an y ser vi ce on so me pr o ducts wh en th e HOT ch assis i s
exp ose d.
5. Don't shor t between the LIVE side ground and ISOLATED
(NEUTRAL) side ground or EARTH side ground when
repairing.
So m e mod el 's p ow er c ircui t is par t ly di f fer en t in t he GN D. Th e
diff er enc e of t he GND is shown by th e LI VE : (") side GND,
th e ISO LATED(NEUTRA L) : (#) sid e GN D an d EAR TH : ( $)
si de GND . Don 't sho rt be tw ee n t he LIVE sid e GN D a nd
ISO LATE D(NEUTRAL) side GND or EARTH side GND a nd
never measure with a meas uring apparatus (oscilloscope etc.)
th e LI VE side GND a nd ISO LATED(NEUTRA L) sid e G ND or
EARTH side GND at the s ame time.
If above note will not be kept, a fuse or any parts will be brok en.
6. If an y re pa ir h as b ee n m ad e to th e ch assis, i t is re com mend ed
th at t he B1 se ttin g sh ou ld b e chec ked or ad j uste d (S ee
ADJU STM ENT OF B 1 POW E R SUPPL Y).
7. The hi g h volt ag e a pp lied t o th e pi ctu re tu be mu st co nfo rm with
that specified in Service manual. Excessive high voltage can
cau se an incr ea se in X- Ray e mi ssion , arc in g an d possi b le
com po ne nt d am ag e, th er ef or e op er ati o n un der excess ive hi gh
vol ta ge c ond it ions sh ou ld be ke pt to a m in imu m, or sh ou l d be
pr eve nt ed. I f seve re arc in g occu rs, r em ove th e AC p ow er
immediately and determine the cause by visual inspection
( in cor rect i nsta lla ti on , cr ac ked o r m elte d high vol tag e h ar ness,
p oor s ol de rin g, etc. ). T o ma in ta in the prop er m ini mum le vel of
sof t X- Ray e mission , com p one nts i n th e hi g h vo ltag e circui tr y
incl ud ing the pictu r e tu be mu st be the exa ct r ep lacem en ts or
alte rn at i ves a ppr o ved b y th e ma nuf actu r er of th e co mp lete
pr od uct.
8. Do n ot c hec k high vol ta ge by d rawin g a n ar c. U s e a hi gh
vol ta ge m ete r or a h igh volt age p ro be w ith a VT VM. Disch ar ge
th e p ictu r e tu be bef or e a tte mp ti ng me ter co nne ction , b y
con nec ting a clip lead t o th e grou nd frame a nd con necting t he
oth er e nd of t he l ead th r oug h a 10 kΩ2W resist or to t he ano de
bu tto n.
9. W hen se rvice i s r equ ir ed, ob ser ve th e o ri g in al lea d dr ess.
Extr a p r ecau tion sh ou ld be gi ven t o assu r e corre ct lea d dres s
in the h i gh volta ge c ircu it ar ea . W her e a sh ort circui t ha s
occu rr e d, th ose c omp on en ts th at i nd ic ate eviden ce of
overheating should be replaced. Always use the
m anu fact ur er's r eplace m ent com p on ents.
10 . Isolation Check
(Safety for Electrical Shock Hazard)
Af ter re- a ssem bling th e pr od uct , always pe rf or m an i so l ati on
ch eck on th e expo sed m eta l p ar ts of th e c abi n et ( ant en na
ter m ina ls, vide o/a ud io in pu t and out put t er mi n als, C on tr ol
knobs, metal cabinet, screwheads, earphone jack, control
sh afts, etc.) to be sur e th e pr o duct is saf e t o op er at e w ith out
d ang er of el ect rica l shoc k.
(1) Dielectric Strength Test
The is ol at io n b etwe en the AC pr ima r y circu it and al l m eta l par ts
exp ose d t o th e us er , par t icu larly an y expo sed m etal p ar t h avi ng
a return pat h to the ch assis sh ould withst and a volta ge of
11 00V AC ( r.m .s.) f or a p er iod of on e sec ond .
(. . . . Withs tand a volta ge of 1100V A C (r.m. s.) to an appliance
r ate d up to 1 20V , a nd 3 00 0V AC ( r .m. s.) t o an ap plianc e r a ted
200V or more, for a period of one second.)
This meth od of test re qu ir es a t est eq uip me nt n ot g en er all y
fou nd i n t he ser vice t ra de.
(2) Leakage Current Check
Plug t he A C line c ord direct ly int o th e AC ou tlet (do not u se a
lin e is ol ati on tr a nsf ormer dur ing t his che ck.). U si ng a "L eaka ge
Cur rent Test er ", m ea sur e t he l ea kag e cur r en t fr om each
exp ose d meta l part of th e ca bi ne t, p ar tic ul arly an y expo sed
metal part having a return path to t he chassis , to a kn own good
ea rt h gr o und (wa ter p i pe, etc.) . A ny l ea kag e cur r en t m ust not
exceed 0. 5mA AC (r .m. s.) .
Howeve r, i n t ro pical a r ea, thi s m ust no t e xc eed 0 .2m A AC
(r.m.s. ).
"
""
"Alte rnate Che ck M ethod
Plug t he A C line c ord direct ly int o th e AC ou tlet (do not u se a
line isolation transformer during this check.). Use an AC
vol tm et er h avi ng 100 0 o hm s per volt or mor e sen siti vit y i n the
fol lo win g ma nne r. C on nec t a 1 50 0Ω1 0W r esi stor pa ra lle led
by a 0.15μF AC- typ e cap acitor b etw e en an exp ose d m eta l
p art an d a kno wn g o od ear th grou nd ( wate r pip e, et c.).
M easu r e th e A C vo ltag e acr oss th e r esi st or wit h t he AC
voltmeter. Move the resist or connection to each exposed metal
part, particularly any exposed metalpart having a returnpath to
th e ch assis , an d mea sur e t he A C volta ge acr oss th e r esisto r.
Now, r eve rs e th e plu g in t he A C out let a nd r ep e at e ach
m easu r em en t. An y vol ta ge me asu re d m ust not exce ed 0.7 5V
AC (r.m. s.) . This corresp on ds t o 0 .5mA A C (r.m. s.).
Howeve r, i n tr op ic al area, thi s m ust n ot excee d 0 .3V AC
(r.m.s. ). This corresp on ds t o 0 .2mA A C (r.m .s.).
0.15μF AC-T YPE
1500Ω10W
GOOD
EARTH
GR OUND
PLACE THIS PROBE
ON E A CH EX PO SE D
ME T AL PA R T
ACVOLTMETER
(HAVING 1000 Ω/V,
OR MOR E SENSITIVITY)
11 . High voltage hold down circuit check.
Af ter rep ai r of th e high vol t ag e h ol d d ow n ci rcui t, th is circu i t
sh al l b e c hec ked to op erate cor rectly.
See ite m "Ho w to check the high voltage hold down
cir cuit".
A V
This mark shows a fast
operating fuse, the
letters indicated below
show the rating.
