Datasheet

SF2D
4
ds_61404_en_sf2d: 180413D
SAFETY STANDARDS
* CSA standard: Certified by C-UL
SAFETY STRUCTURE OF SF RELAYS
UL/C-UL (Recognized) TÜV (Certified) SEV
File No. Contact rating File No. Rating File No. Contact rating
E120782* 6A 250V AC
6A 24V DC
968 EZ 116.00 01 (SF2D)
968 EZ 113.00 01 (SF4D)
8A 24V DC
6A 230V AC
01, 1851 6A 230V AC
6A 24V DC
Structure Operation
1. Forced operation method
(2 Form A 2 Form B,
4 Form A 4 Form B types)
The two contacts “a” and “b” are coupled with the same card. The operation
of each contact is regulated by the movement of the other contact.
Even when one contact is welded closed, the other
maintains a gap of greater than 0.5 mm .020 inch.
In the diagram on the left, the lower contact “b” have
welded but the upper contact “a” maintain at a gap of
greater than 0.5 mm .020 inch.
Subsequent contact movement is suspended and the
weld can be detected
2. Separate chamber method
(2 Form A 2 Form B,
4 Form A 4 Form B types)
In independent chambers, the contacts “a” and “b” are kept apart by a body/
case separator or by the card itself.
Prevents shorting and fusing of springs and spring
failure owing to short-circuit current.
As shown on the diagram on the left, even if the
operating springs numbered 1 and 2 there is no
shorting between “a” and “b” contacts.
3. 2 Form A 2 Form B contact
4 Form A 4 Form B contact
Structure with independent COM contact of 2 Form A 2 Form B and
4 Form A 4 Form B contacts.
Independent COM enables differing pole circuit
configurations. This makes it possible to design
various kinds of control circuits and safety circuits.
This SF relay design ensures that
subsequent operations shut down and
can automatically return to a safe state
when the SF relay suffers overloading
and other circuit abnormalities
(unforeseen externally caused circuit or
device breakdowns, end of life incidents,
and noise, surge, and environmental
influences) owing to contact welding,
spring fusion or, in the worst-case
scenario, relay breakdown (coil rupture,
faulty operation, faulty return, and fatigue
and breakage of the operating spring and
return spring), and even in the event of
end of life.
Min. 0.5 mm .020 inch
Contact a
Card
Weld
Contact b
Case separator
Card
Contact a
Body
separator
Contact b
1
2