Panasonic is part of a large worldwide groupselling relays and associated switching products under different brand names in different territories.The conditions of use in some territories may differ from those customary in Europe. In particular there are often major differences in regard to national and international specifications, such as UL, CSA, VDE, SEV, EVE, SEMKO, etc. Thus, when considering contact loads as stated in this catalogue (e.g. 10 A, 30 VDC for the SP relay) its hould be understood that these values are not necessarily an absolute maximum but tested ratings. Mostly the stated value has been tested for a certain life expectancy as stated by the manufacturer or the respective test house. Thus, under different conditions, the stated “maximum” may, in practice, be safely exceeded.
Asshownonthediagramontheleft, evenifthe
operatingspringsnumbered 1and2thereisno
shortingbetween“a”and“b”contacts.
Subsequentcontact movementissuspendedandthe
weldcanbedetected
Thetwocontacts“a”and“b”arecoupledwiththesamecard.020inch.5mm.
3.
Structure Operation
1.
Independent COMenablesdifferingpolecircuit
configurations.
Inindependentchambers,thecontacts“a”and“b”arekeptapart byabody/
caseseparatororbythecarditself.1 10376
99. 3FormA1FormBcontact Structurewithindependent COMcontact of(3FormA1FormB), contacts.
F d
I a
m .
If the No. Contact rating FileNo. contact welds.020inch.
576
Energized (whenno. 6A250VAC R9919003(SF3) 6A250VAC 97.
ds 61405 sf3: 180413D
.5mm.1 10197.5mm.01
6A250VAC
SAFETY STRUCTURE RELAYS
T t
s d
c e
w g
a s
( r
d ,
a l
i ,
s e
s ,
f e
a d
r f
e .SF3
SAFETY STANDARDS
UL/C-UL(Recognized) CSA(Certified) TÜV(Certified) SEV
FileNo. Contact rating FileNo. Forcedoperationmethod
(3FormA1FormBtypes)
Evenwhenonecontact isweldedclosed,theother
maintainsagapofgreaterthan0.020inch. 3contact iswelded)
Becausetheweldedcontactspringisattachedtothe
card,thearmaturehasbecomeinoperative.
2. Rating FileNo. Contact rating
E43149 6A250VAC LR26550etc. Thismakesitpossibletodesign
variouskindsofcontrol circuitsandsafetycircuits.
Eachofthethreeform“a”contacts(No.
Inthediagramontheleft,thelowercontact “b”have
weldedbuttheuppercontact “a”maintainatagapof
greaterthan0.Theoperation
ofeachcontact isregulatedbythemovementoftheothercontact. 1,2,and4)
maintainagapofgreaterthan0. Separatechambermethod
(3FormA1FormBtypes)
Preventsshortingandfusingofspringsandspring
failureowingtoshort-circuit current
