Datasheet

7
B3W-9B3W-9
Safety Precautions
Note: Refer to Safety Precautions in Tactile Switches (Cat. No. X037) for details on general safety precautions.
■
Precautions for Correct Use
Electrical Standards
Use the Switch within the rated voltage and current ranges, other-
wise the Switch may have a shortened life expectancy, radiate
heat, or burn out. This particularly applies to the instantaneous
voltages and currents when switching.
Soldering
1. Soldering Precautions
• Before any kind of soldering, test to confirm that soldering can be
performed properly. Otherwise the Switch may be deformed by
the soldering heat depending on the type of PCB, pattern, or
lands of the PCB.
• Do not solder the Switch more than twice, including rectification
soldering. Wait for at least five minutes between the first and sec-
ond soldering to allow the temperature to return to normal. Con-
tinuous soldering may cause the casing to melt or deteriorate the
Switch characteristics.
2. Automatic Soldering Baths (Wave Soldering)
• Soldering temperature: 260°C max.
• Soldering time: 5 s max. for a 1.6-mm thick single-side PCB
• Preheating temperature: 100°C max. (ambient temperature)
• Preheating time: Within 60 s
• Precautions
Make sure that no flux will rise above the level of the PCB. Also
make sure that flux is not applied to the switch terminals or to the
mounting surface of the PCB.
If flux overflows onto the mounting surface of the PCB, it may en-
ter the Switch and cause a malfunction.
3. Manual Soldering
• Soldering temperature: 350°C max. at the tip of the soldering iron
• Soldering time: 3 s max. for a 1.6-mm thick, single-side PCB
• Precautions: Before soldering the Switch on a PCB, make sure
that there is no unnecessary space between the
Switch and the PCB.
Washing
Standard Switches are not sealed, and cannot be washed. Doing
so will cause the washing agent, together with flux or dust parti-
cles on the PCB, to enter the Switch, resulting in malfunction.
PCBs
The Switch is designed for a 1.6-mm thick, single-side PCB.
Using PCBs with a different thickness or using double-sided,
through-hole PCBs may result in loose mounting, improper inser-
tion, or poor heat resistance in soldering. These effects will occur,
depending on the type of holes and patterns of the PCB. There-
fore, it is recommended that a verification test is conducted before
use.
Handling
1. Usage Environment
Before installing the Switch, make sure that the area of installa-
tion is not subject to corrosive gases emitted from surrounding
parts.
Do not use in areas subject to high temperatures, high humidity,
or toxic gases such as sulfuric gas (H
2
S, SO
2
), ammonia gas
(NH
3
), nitric gas (HNO
3
), or chlorine gas (CI
2
). It can cause corro-
sive damage to the contacts and result in malfunction.
If there is silicon in the atmosphere, it may stop the contacts from
functioning properly.
If silicon products, such as silicon oil, silicon filler, or silicon wires,
are used in the surrounding area, install a contact protection cir-
cuit to prevent arching or remove the silicon source.
The following situations may cause water to enter inside the
Switch, resulting in a malfunction due to contact failure or corro-
sion.
• Using the Switch in an outdoor environment where it is exposed
to water drops for an extended period of time.
• Using the Switch in an underwater setting where it is subject to
strong water pressure.
Do not use Switches that have been dropped. The mating section
or other internal parts may be damaged, resulting in malfunction.
Operation
Do not repeatedly operate the Switch with excessive force. Apply-
ing excessive pressure or applying additional force after the
plunger has stopped may deform the disk spring of the Switch,
resulting in malfunction.
Be sure to set up the Switch so that the plunger will operate in a
straight vertical line.
If the plunger is pressed of-center or from an angle it may cause
deformation or damage to some parts. This may result in deterio-
ration of durability or malfunction.
Dust Protection
Do not install or use Switches in dust-prone environments. If a
Switch must be used in this kind of environment, use a protective
sheet or take other measures to protect it against dust.
Note: Switches with high-brightness green (HG) or blue (B)
LEDs are susceptible to static electricity. Be careful when
handling a Switch with these LEDs as it may cause the
Switch to breakdown.