Technical Terminology & Cautions for Use
–3–
AECTB38E 201701-T
CAUTIONS FOR USE
■ Environment of use
1) Please consult us when using under the following conditions:
• Environments where hydrogen sulfide or other corrosive gases
are present.
• Environments where gasoline, thinner or other flammable,
explosive gases are present.
• Dusty environments (for non-seal type snap action switches).
• Use in environments not in the prescribed temperature or
humidity range.
• Places with low air pressure.
2) Unless specified the product will not be constructed to
withstand water, oil or explosions. Please inquire if you intend to
use the product in special applications.
■ Usage, storage, and transport conditions
1) During usage, storage, or transportation, avoid locations
subject to direct sunlight and maintain normal temperature,
humidity, and pressure conditions.
2) The allowable specifications for environments suitable for
usage, storage, and transportation are given below.
(1) Temperature: The allowable temperature range differs for
each switch, so refer to the switch’s individual specifications.
(2) Humidity: 5 to 85% R.H.
(3) Pressure: 86 to 106 kPa
The humidity range varies with the temperature. Use within the
range indicated in the graph below.
(The allowable temperature depends on the switch.)
• Condensation will occur inside the switch if there is a sudden
change in ambient temperature when used in an atmosphere of
high temperature and high humidity. This is particularly likely to
happen when being transported by ship, so please be careful of
the atmosphere when shipping. Condensation is the
phenomenon whereby steam condenses to cause water
droplets that adhere to the switch when an atmosphere of high
temperature and humidity rapidly changes from a high to low
temperature or when the switch is quickly moved from a low
humidity location to one of high temperature and humidity.
Please be careful because condensation can cause adverse
conditions such as deterioration of insulation, coil cutoff, and
rust.
• Condensation or other moisture may freeze on the switch when
the temperatures is lower than 0°C 32°F. This causes problems
such as sticking of movable parts or operational time lags.
• The plastic becomes brittle if the switch is exposed to a low
temperature, low humidity environment for long periods of time.
• Storage for extended periods of time (including transportation
periods) at high temperatures or high humidity levels or in
atmospheres with organic gases or sulfide gases may cause a
sulfide film or oxide film to form on the surfaces of the contacts
and/or it may interfere with the functions. Check out the
atmosphere in which the units are to be stored and transported.
• In terms of the packing format used, make every effort to keep
the effects of moisture, organic gases and sulfide gases to the
absolute minimum.
■ Wiring
1) When using a PC board terminal switch as soldering
terminals, use thin lead wires and be sure to wind them on the
terminals before soldering.
2) Cautions when soldering
Perform soldering quickly in accordance with the specified
conditions. Be careful not to let flux flow into the product. When
no instruction is specified, use a 60 W soldering iron (350°C)
and complete soldering within five seconds. Do not pull on the
lead wires immediately after soldering. Wait some time before
verifying.
■ Others
1) Failure modes of switches include short-circuiting, open-
circuiting and temperature rises. If this switch is to be used in
equipment where safety is a prime consideration, examine the
possible effects of these failures on the equipment concerned,
and ensure safety by providing protection circuits or protection
devices. In terms of the systems involved, make provision for
redundancy in the design and take steps to achieve safety
design.
2) The ambient operating temperature (and humidity) range
quoted is the range in which the switch can be operated on a
continuous basis: it does not mean that using the switch within
the rating guarantees the durability performance and
environment withstanding performance of the switch. For details
on the performance guarantee, check the specifications of each
product concerned.
3) Even if 2-pole, 3-pole or 4-pole switches are used as single-
pole switches in order to increase contact reliability, please keep
the maximum current no higher than the rated value.
4) If there is the possibility of a short between poles, please use
an in-phase circuit as shown below or provide a spare pole.
5) Be careful not to drop the product as this may cause loss of
functionality.
6) Do not apply an unreasonable vertical force against the
direction of operation of the product.
7) Use your hand to operate the actuator.
(Operation using a tool such as a screwdriver or hammer can
cause breakdown.)
Tolerance range
(Avoid
condensation when
used at temperatures
higher than 0°C 32°F)
(Avoid freezing when
used at temperatures
lower than 0°C 32°F)
85
5
–40
–40
0
+32
+85
+185
Temperature, °C °F
Humidity, %R.H.
Bad example
Good example (1)
Good example (2)
Load 1
Load 1
Heteropolar circuit
In-phase circuit
Load 2
Load 1
Spare pole
Load 2
Load 2
