PCSW303B3A000 TDK Corp., PCSW303B3A000 Datasheet - Page 2

• Manufacturer Part Number: PCSW303B3A000
• Description: Door Operation Sensors Switch Built-in Magnet Door Latch Pcsw Series
• Manufacturer: TDK Corp.

OPERATION PRINCIPLES
A TYPE SWITCH CONTACTS OPEN (OFF)
1. Door closed
Closing the door brings its ferromagnetic attraction plate into con-
tact with the door latch housing. This causes the magnetic flux
generated from the magnet in the housing to flow across both
yokes, through the attraction plate on the door. This holds the door
closed. Since the magnetic flux now flows through the attraction
plate, the flux available to the reed switch drops below the release
point of the switch, and the contacts open (OFF).
2. Door open
When the door is open, its ferromagnetic attraction plate is sepa-
rated from the door latch housing. This causes the magnet’s flux to
leak through both yokes of the magnetic circuit. Leakage occurs
from an actuating projection at the reed switch side of the yoke to a
diagonally-positioned actuating projection. This makes the flux
through the reed switch rise beyond the closing point of the switch,
causing it to close (ON).
B TYPE SWITCH CONTACTS CLOSED (ON)
1. Door closed
Closing the door brings its ferromagnetic attraction plate into con-
tact with the door latch housing. This causes the magnetic flux
generated from the magnet in the housing to flow across both
yokes, through the attraction plate on the door. This holds the door
closed. Since the magnetic flux from the magnet now flows
through the attraction plate, only leakage flux is available to the
reed switch. However, a submagnet provided in the upper part of
the reed switch is unaffected, and its magnetic flux causes the
reed switch to close (ON).
2. Door open
When the door is open, its ferromagnetic attraction plate is sepa-
rated from the door latch housing. This causes the magnet’s flux to
leak through both yokes of the magnetic circuit. Leakage occurs
from an actuating projection at the reed switch side of the yoke to a
diagonally-positioned actuating projection. The flux from the main
magnet through the reed switch rises. However, the magnetic flux
from the submagnet interferes with this rising flux leakage from the
main magnet, counteracting it. The result is that the overall
magnetic flux through the reed switch now drops below the releas-
ing point of the switch, causing the contacts to open (OFF).
INSTALLATION EXAMPLES
• All specifications are subject to change without notice.
1
3
SPCC or similar
material
Molded plastic resin
or other similar
non-magnetic material
2
4
Molded plastic resin or other
similar non-magnetic material
Dimensions in mm
GUIDELINES FOR RELIABLE OPERATION
• Do not drop or strike these products. They contain glass-housed
• Do not apply excessive force to leads during soldering.
• Do not store or use these products under conditions of intense
• Do not overload the holding ability of the latch. Forces in excess
• Do not allow foreign magnetic materials, substances or fillings to
• The housings of these products do not incorporate magnetic
RECOMMENDED ATTRACTING PLATES
TDK SW Catches(Sensing Door Latches) utilize changes in
magnetic flux for switching operation. Therefore, the shape of the
attracting plate can influence operation. The recommended attract-
ing plate shape is shown below.
The magnetic pull force of these products was determined using a
TDK standard deadweight which is a cylindrically-shaped piece of
iron. Therefore, when iron attracting plates of 1 to 2mm thickness
are used, the magnetic pull will be less than the values given
above.
reed switches.Excessive impact may result in breakage. Even if
the glass envelope is not broken, impact may cause the switch-
ing characteristics to change.
static magnetic fields, alternating magnetic fields, or pulsed
magnetic fields.
of 49N may deform the housing.
stick to the magnetized attracting surface of the housing. This
will cause a gap between the housing and the attracting plate
when the door or panel is closed, resulting in unreliable opera-
tion. Use with caution in locations where such foreign material
may be a factor. Removal of any attracted foreign material
restores normal operation.
shielding. Mounting face A is designed to be in contact with
ferromagnetic material. However, placing the housing’s other
faces in contact with or in close proximity to magnetic materials
may cause characteristics to change. Contact TDK Engineering
if your application requires placement near magnetic materials.
1.6min.
Dimensions in mm
002-01 / 20070227 / ec311_pcsw.fm
The following shape should
be avoided as it poses a
greater risk of unstable
operation.
(2/2)