Low-torque Basic Switch
D2MC
Highly Reliable Rotary-action Switch for
Low Torque Operation (0.5 m N S m
{5.1 gf S cm})
0.5-A rated model employs crossbar gold-alloy
contacts for excellent contact reliability in the micro
load range.
Long life (10,000,000 mechanical operations min.)
through use of a movable coil spring.
RC
Ordering Information
Model Number Legend
D2MC-jjj
1
2
3
3.
1.
Ratings
5: 5 A at 250 VAC
0.1: 0.5 A at 30 VDC
2.
Maximum Operating Torque (OTq)
E: 0.5 mN S m {5.1 gf S cm} max.
F: 0.75 mN S m {7.6 gf S cm} max.
H: 1.00 mN S m {10.2 gf S cm} max.
Direction of Actuator
None: Clockwise
L:
Counterclockwise
List of Models
Direction of actuation
Clockwise
Counterclockwise
Note:
156
OTq max.
5A
0.5 A
0.5 m N S m {5.1 gf S cm}
D2MC-5E
D2MC-01E
0.75 m N S m {7.6 gf S cm}
D2MC-5F
D2MC-01F
1.00 m N S m {10.2 gf S cm}
D2MC-5H
D2MC-01H
0.5 m N S m {5.1 gf S cm}
D2MC-5EL
D2MC-01EL
0.75 m N S m {7.6 gf S cm}
D2MC-5FL
D2MC-01FL
1.00 m N S m {10.2 gf S cm}
D2MC-5HL
D2MC-01HL
All the models listed here are supplied without actuator lever. If an actuator lever is required, please order separately by indicating the
model number of the actuator lever (CAA1M). Refer to page 160.
D2MC
D2MC
Specifications
Ratings
Item
Model
D2MC-5
D2MC-01
Note:
Resistive load
Rated voltage
125 VAC
5A
250 VAC
5A
125 VAC
0.5 A
30 VDC
0.5 A
The ratings values apply under the following test conditions:
Ambient temperature: 20±2°C
Ambient humidity: 65±5%
Operating frequency: 30 operations/min.
Characteristics
Item
D2MC-5
D2MC-01
Operating speed
1° to 360°/sec
Operating frequency
Mechanical: 240 operations/min max.
Electrical: 30 operations/min max.
Insulation resistance
100 MΩ min. (at 500 VDC)
Contact resistance
(initial value)
20 mΩ max.
Dielectric strength
600 VAC, 50/60 Hz for 1 min between terminals of same polarity
1,500 VAC, 50/60 Hz for 1 min between current-carrying metal parts and ground, and between each
terminal and non-current-carrying metal part
Vibration resistance
(see note 2)
Malfunction: 10 to 55 Hz, 1.5-mm double amplitude
Shock resistance
(see note 2)
Destruction: 1,000 m/s2 {100 G} max.
Malfunction: Models with OTq of 0.5 mN S m: 100 m/s2 {10 G} max.
Models with OTq of 0.75 mN S m: 100 m/s2 {10 G} max.
Models with OTq of 1.00 mN S m: 200 m/s2 {20 G} max.
Durability (see note 3)
Mechanical: 10,000,000 operations min.
(60 operations/min)
Electrical: 100,000 operations min.
(30 operations/min)
Degree of protection
IEC IP40
Degree of protection
against electric shock
Class I
Proof tracking index (PTI)
175
Ambient operating
temperature
–25°C to 80°C (at ambient humidity of 60% max.) (with no icing)
Ambient operating
humidity
35% to 85% max. (for 5°C to 35°C)
Weight
Approx. 10 g
Note:
100 mΩ max.
Mechanical: 10,000,000 operations min.
(60 operations/min)
Electrical: 100,000 operations min.
(30 operations/min, 125 VAC,
30 VDC 0.1 A)
1. The data given above are initial values.
2. Malfunction: 1 ms max.
3. For testing conditions, contact your OMRON sales representative.
157
D2MC
D2MC
Approved Standards
Contact Form
Consult your OMRON sales representative for specific models with
standard approvals.
SPDT
UL508 (File No. E41515)/
CSA C22.2 No. 55 (File No. LR21642)
Rated voltage
D2MC-01
D2MC-5
125 VAC
0.5 A
5A
250 VAC
---
5A
30 VDC
0.5 A
---
Contact Specifications
Item
Contact
Inrush
currentt
D2MC-5
Rivet
Crossbar
Material
Silver alloy
Gold alloy
Gap (standard value)
0.5 mm
NC
15 A max.
0.5 A max.
NO
7 A max.
0.5 A max.
160 mA at
5 VDC
1 mA at
5 VDC
Minimum applicable load
(see note)
Note:
D2MC-01
Specification
For more information on the minimum applicable load, refer
to Using Micro Loads on page 160.
Engineering Data (Reference Values)
Ambient temperature: 20±2°C
Ambient humidity: 65±5%
Without load
Operating frequency: 240 operations/minute
Overtravel
158
Electrical Durability
Number of operations (x10 4)
Number of operations (x10 4)
Mechanical Durability
Ambient temperature: 20±2°C
Ambient humidity: 65±5%
Operating frequency:
D2MC-01: 60 operations/min
D2MC-5: 20 operations/min
0.1 A 125 VAC (cosφ=1)
(D2MC-01)
0.5 A 125 VAC (cosφ=1)
(D2MC-01)
5 A 250 VAC (cosφ=1)
(D2MC-5)
Switching current (A)
D2MC
D2MC
Dimensions
Mounting Holes
Note:
All units are in millimeters unless otherwise indicated.
Two, 3.1-dia. mounting holes or
M3 screw holes
8.7 ± 0.1
23.8 ± 0.1
Dimensions and Operating Characteristics
Note:
1. All units are in millimeters unless otherwise indicated.
2. The j in the model number are for the Ratings and OTq code.
3. The angle given for the free position (FP) is the angle made with the horizontal.
Clockwise
Model
D2MC-5E
D2MC-01E
D2MC-5F
D2MC-01F
OTq
max.
0.5 mN S m
gf S cm}}
{{5.1 g
0.75 mN S m
gf S cm}}
{{7.6 g
1.0 mN S m
{{10.2 gf
g S cm}}
RTq min.
0.06 mN S m
{0.6 gf S cm}
0.09 mN S m
{0.9 gf S cm}
0.13 mN S m
{1.3 gf S cm}
PT max.
21°
21°
21°
OT min.
17°
17°
17°
MD min.
3°
3°
3°
RT min.
5°
5°
5°
TT min.
38°
FP
15±3° (see note 3)
D2MC-jj
3.1±0.05 dia.
Operating
direction
4±0.1 dia.
t=0.8
Quick-connect terminals (#205)
Counterclockwise
Model
D2MC-jjL
3.1±0.05 dia.
Operating
direction
D2MC-5EL
D2MC-01EL
D2MC-5FL
D2MC-01FL
D2MC-5H
D2MC-01H
D2MC-5HL
D2MC-01HL
OTq
max.
0.5 mN S m
{{5.1 g
gf S cm}}
0.75 mN S m
{{7.6 g
gf S cm}}
1.0 mN S m
{{10.2 gf
g S cm}}
RTq min.
0.06 mN S m
{0.6 gf S cm}
0.09 mN S m
{0.9 gf S cm}
0.13 mN S m
{1.3 gf S cm}
PT max.
21°
21°
21°
OT min.
17°
17°
17°
MD min.
3°
3°
3°
RT min.
5°
5°
5°
TT min.
38°
FP
15±3° (see note 3)
4±0.1 dia.
t=0.8
Quick-connect terminals (#205)
159
D2MC
D2MC
Accessories (Sold Separately)
Actuator Lever
2. Push the lever down in the direction of the groove in the rotary
disc.
CAA1M for Snap-on Mounting
50±1
Rotary shaft
0.6-dia. stainless-steel wire
In addition to the standard wire lever model shown here, various
other levers are available upon request.
Mounting Actuator Lever
1. Insert the end of the actuator lever into the hole in the rotary
disc.
Designing Own Actuator
If you decide to make your own actuator lever, the materials used
should be stainless steel, piano wire, hard aluminum wire, etc.
There are no restrictions on the tip shape or length of the actuator
lever. However, if the lever is too long, improper switch resetting or
contact chattering may occur. Therefore, the shape of lever as
shown below is suitable.
1.6
0.6 dia. stainless-steel wire
3.6
Center of
rotating axis
l
The appropriate value of dimension (l) from the fulcrum is 50 mm.
Precautions
Refer to pages 26 to 31 for common precautions.
Correct Use
Mounting/Soldering
Use M3 mounting screws with plane washers or spring washers to
mount the switch. Tighten the screws to a torque of 0.20 to
0.29 N S m {2 to 3 kgf S cm}.
Do not change the operating position by modifying the actuator.
Using Micro Loads
For details, refer to General Information.
ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.
To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.
Cat. No. B051-E1-07B
160
General Information
General Information
Correct Use
No.
Area
No.
Item
Using Switches
2
Selecting Correct Switch
3
Electrical
C diti
Conditions
4
5
6
7
Mechanical
C diti
Conditions
Mounting
g
Operation
p
and
d St
Storage
Environment
1
Load
2
Application of Switch to
Electronic Circuits
3
Switches for Micro Loads
4
Contact Protective
Circuit
27
1
Operating Stroke Setting
28
2
Switching Speed and
Frequency
3
Operating Condition
4
Operating Method
1
Securing
2
Terminal Connections
3
Soldering Precautions
1
Handling
2
Operating Environment
3
Storage Environment
Switch Trouble and Corrective Action
29
30
31
Using Switches
•
•
Electrical Conditions
Page
26
1
When switches are actually used, unforeseen accidents may
occur. Before using a switch, perform all possible testing in
advance.
Load
The switching capacity of a switch significantly differs depending on
whether the switch is used to break an alternating current or a direct
current. Be sure to check both the AC and DC ratings of a switch.
The control capacity will drop drastically if it is a DC load. This is because a DC load, unlike an AC load, has no current zero cross point.
Therefore, if an arc is generated, it may continue for a comparatively
long time. Furthermore, the current direction is always the same,
which results in contact relocation phenomena, and the contacts
hold each other with ease and will not separate if the surfaces of the
contacts are uneven.
If the load is inductive, counter-electromotive voltage will be generated. The higher the voltage is, the higher the generated energy is,
which increase the abrasion of the contacts and contact relocation
phenomena. Make sure to use a switch within the rated conditions.
If a switch is used for switching both micro and high-capacity loads,
be sure to connect relays suitable to the loads.
The rated loads of a switch are according to the following conditions:
Inductive Load: A load having a minimum power factor of 0.4 (AC) or
a maximum time constant of 7 ms (DC).
Lamp Load: A load having an inrush current ten times the
steady-state current.
Motor Load: A load having an inrush current six times the steadystate current.
Note: It is important to know the time constant (L/R) of an inductive load in a DC circuit.
Inrush Current
I
(A)
Unless otherwise specified, ratings and performances given in
this catalog are for standard test conditions (i.e., 15 to 35_C,
25% to 75% humidity, and 86 to 106 kPa atmospheric pressure).
When performing testing in the actual application, always use
the same conditions as will be used in actual usage conditions for
both the load and the operating environment.
•
Reference data provided in this catalog represents actual
measurements from production samples in graph form. All
reference data values are nominal.
•
All ratings and performance values provided in this catalog are
the results of a single test each rating and performance value
therefore may not be met for composite conditions.
Selecting Correct Switch
Select an appropriate switch for the operating environment and load
conditions.
•
Use the Selection Guide to select a suitable switch for the rated
current, operating load, actuator type, and operating environment.
•
It is not recommended to use a switch for a large current to switch
a micro current, in terms of contact reliability. Select a switch that
is suitable for the current actually being switched.
•
Use a sealed switch in environments subject to water, other
liquids and excessive dirt or dust.
i (Inrush current)
io (Steadystate current)
t
Application of Switch to Electronic Circuits
The Basic switch may have contact bouncing or chattering in
switching, thus generating noise or pulse signals that may interfere
the operation of electronic circuits or audio equipment. To prevent
this, take the following countermeasures.
•
Design the circuits so that they include appropriate CR circuits to
absorb noise or pulse signals.
•
Use switches with gold-plated contacts for micro loads, which
are more resistive to environmental conditions.
Switches for Micro Loads
If a switch for a general load is used for switching a micro load, it may
cause contact failures. Be sure to select a switch within the permissible range. Even if a switch for a micro load is used within the permissible range, the inrush current of the load may deteriorate the
contacts, thus decreasing the durability of the switch. Therefore, if
necessary, insert a proper contact protective circuit.
26
General Information
General Information
Contact Protective Circuit
When a switch is used under high humidity, arcs resulting from certain types of load (e.g., inductive loads) will generate nitrious oxides
and, with mater the nitrious oxides will become nitric acid, which will
corrode internal metal parts and may cause malfunctions. Always
use a contact protective circuit according to information provided in
the following table when using a switch under circuit conditions of
frequent switching and arcing.
The use of a contact protective circuit may delay the response time
of the load.
Apply a contact protective circuit (surge killer) to extend contact durability, prevent noise, and suppress the generation of carbide or nitric acid due to arc. Be sure to apply the contact protective circuit
properly, otherwise an adverse effect may result. Some typical
examples of contact protective circuit are described in the following
table.
Typical Examples of Contact Protective Circuits (Surge Killers)
Applicable
current
Circuit example
CR
circuit
Power supply
Power
supply
DC
Yes
Power supply
Inductive
load
The capacitor suppresses the spark
discharge of current when the contacts are
open. The resistor limits the inrush current
when the contacts are closed again.
Consider these roles of the capacitor and
resistor and determine the ideal
capacitance and resistance values from
experimentation.
Use a capacitor with a dielectric strength
between 200 and 300 V. When AC is
switched, make sure that the capacitor has
no polarity.
If, however, the ability to control arcs
between contacts is a problem for high DC
voltage, it may be more effective to
connect a capacitor and resistor between
the contacts across the load. Check the
results by testing in the actual application.
The operating time will increase if the
load is a relay or solenoid.
It is effective to connect the CR circuit
in parallel to the load when the power
supply voltage is 24 or 48 V and in
parallel to the contacts when the
power supply voltage is 100 to 200 V.
No
Yes
Energy stored in the coil is changed
into current by the diode connected in
parallel to the load. Then the current
flowing to the coil is consumed and
Joule heat is generated by the
resistance of the inductive load. The
reset time delay in this method is
longer than that of the CR method.
The diode must withstand a peak inverse
voltage 10 times higher than the circuit
voltage and a forward current as high as or
higher than the load current.
No
Yes
This method will be effective if the
reset time delay caused by the diode
method is too long.
Zener voltage for a Zener diode must be
about 1.2 times higher than the power
source since the load may not work under
some circumstances.
Yes
Yes
This method makes use of
constant-voltage characteristic of the
varistor so that no high-voltage is
imposed on the contacts. This method
causes a reset time delay more or
less. It is effective to connect varistor
in parallel to the load when the supply
voltage is 24 to 48 V and in parallel to
the contacts when the supply voltage
is 100 to 200 V.
Select the varistor so that the following
condition is met for the cut voltage Vc. For
AC currents, the value must be multiplied
by √2.
Inductive
load
Varistor
method
C: 0.5 to 1 µF per switching current (1 A)
R: 0.5 to 1 Ω per switching voltage (1 V)
The values may change according to the
characteristics of the load.
Yes
Inductive
load
Power supply
When AC is switched, the
load impedance must be lower than the C and R impedance.
Element selection
Yes
Inductive
load
Power supply
Note:
Inductive
load
Diode
method
Diode
and
Zener
diode
method
AC
See
note.
Feature
Vc > (Current Voltage x 1.5)
If Vc is set too high, however, the voltage
cut for high voltages will no longer be
effective, diminishing the effect.
Do not apply contact protective circuit as shown below.
Incorrect
Power
supply
Load
This circuit effectively suppresses arcs when
the contacts are OFF. The capacitance will be
charged, however, when the contacts are OFF.
Consequently, when the contacts are ON again,
short-circuited current from the capacitance
may cause contact weld.
Incorrect
Load
Power
supply
This circuit effectively suppresses
arcs when the contacts are OFF.
When the contacts are ON again,
however, charge current flows to
the capacitor, which may result in
contact weld.
27
General Information
General Information
Switching Speed and Frequency
Mechanical Conditions
Operating Stroke Setting
Contact force
Operating force
The setting of stroke is very important for a switch to operate with
high reliability.
The chart below shows the relationship among operating force,
stroke, and contact force. To obtain high reliability from a switch, a
switch actuator must be manipulated within an appropriate range of
operating force.
Be sure to pay the utmost attention when mounting a switch.
The switching frequency and speed of a switch have a great influence on the performance of the switch. Pay attention to the following.
•
If the actuator is operated too slowly, the switching operation
may become unstable, causing contact failures or contact
welding.
•
If the actuator is operated too quickly, the switch may be
damaged by shock.
•
If the switching frequency is too high, the switching of the
contacts cannot catch up with the operating speed of the
actuator.
•
Stroke
FP
Release
Stroke
Release
TTP
Make sure that the operating body is set so that the actuator should
return to the free position when the operating body has moved if a
switch is used to form a normally closed (NC) circuit. If a switch is
used to form a normally open (NO) circuit, the operating body must
move the switch actuator to the distance of 70% to 100% of the rated
overtravel (OT) of the switch.
Operating
body
PT (Pretravel)
Install a stopper.
If the operating frequency is extremely low (i.e., once a month or
less frequent), a film may be generated on the surface of the
contacts, which may cause contact failures.
The permissible switching speed and switching frequency of a
switch indicate the operational reliability of the switch. The durability
of a switch is based on operation under specific conditions regarding the switching speed and switching frequency. The durability of a
switch may not meet the durability due to conditions even if the
switch is operated within the permissible switching speed and frequency ranges. Test a switch sample under the actual conditions to
ascertain its durability.
Operating Condition
Do not leave a switch with the actuator depressed for a long time,
otherwise the parts of the switch may soon deteriorate and the
changes of its characteristics operating may result.
Operating Method
The operating method has a great influence on the performance of a
switch. Consider the following before operating a switch.
•
Design the operating body (i.e., cam or dog) so that it will operate
the actuator smoothly. If the actuator snaps backwards quickly or
receives shock due to the shape of the operating body, its
durability may be deteriorated.
FP (Free position)
OP (Operating position)
Incorrect
OT (Overtravel)
Snap-back
Shock operation
TTP
(Total travel position)
Correct
If stroke is set in the vicinity of the operating position (OP) or the releasing position (RP), contact force may become unstable. As a result, the switch cannot ensure high reliability. Furthermore, the
switch may malfunction due to vibration or shock.
If stroke is set exceeding the total travel position (TTP), the moment
of inertia of the operating body may damage the actuator or the
switch itself, and the stress applied to the moving spring inside the
switch will increase and then, the durability of the switch may be deteriorated.
Incorrect
28
Correct
General Information
General Information
Incorrect
•
Do not modify the actuator. If the actuator is modified, excessive
external force may be applied to the internal switch mechanism,
characteristics may change, and the switch may stop
functioning.
•
If an external actuator is used as an operating object, check the
material and thickness of the lever to make sure that the force
applied to the lever is within the permissible range.
Snap-back
Shock operation
Mounting
Correct
•
Securing
Make sure that no improper force is applied to the actuator,
otherwise the actuator may incur local abrasion. As a result, the
actuator may become damaged or its durability may be
deteriorated.
Incorrect
Roller
Correct
When mounting a switch, be sure to use the specified mounting
screws and tighten the screws with flat washers or spring washers
securely.
However, the switch housing may incur crack damage if it comes
into contact with the spring washers directly. In that case make sure
that the flat washers come into contact with the switch housing as
shown below. Do not subject the switch to excessive shock or highfrequency vibrations when mounting (e.g., do not use an impact
driver) as it may cause contacts stick or switch damage.
Incorrect
Screw
Correct
Flat washer
Spring washer
Resin
Dog
Do not modify the switch in any way, for example, by widening the
mounting holes.
Operating
body
Operating
body
: Correct
: Incorrect
•
•
Make sure that the operating body moves in a direction where
the actuator moves. If the actuator is a pin plunger type, make
sure that the operating body presses the pin plunger vertically.
Operate the actuator of a hinge roller lever or simulated hinge
lever type in the direction shown below.
Incorrect
Correct
Locking Agent
If glue or locking agent is applied, make sure that it does not stick to
the moving parts or intrude into the inside of the switch, otherwise
the switch may have operating failure or contact failure. Some types
of glue or locking agent may generate gas that has a bad influence
on the switch. Pay the utmost attention when selecting glue or locking agent.
Wiring
Make sure that the lead wires are connected with no inappropriate
pulling force.
Mounting Location
Be sure not to mount a switch in locations where the switch may be
actuated by mistake.
Maintenance and Inspection
Make sure that a switch is mounted in locations that allow easy
inspection or replacement of the switch.
Mounting Direction
When using a switch with a low operating force mounted with a long
lever, make sure that the switch is mounted in the direction where
the weight of the lever is not applied to the pushbutton directly,
otherwise the switch may have releasing failures.
Terminal Connections
•
Set the angle of the cam or dog (θ) for roller levers and similar
actuators to the range between 30_ and 45_. If the angle is too
large, an abnormally large horizontal stress will be applied to the
lever.
Solder Terminals
When soldering lead wires to a switch, make sure that the temperature of the iron tip is 380°C maximum. Improper soldering may
cause abnormal heat radiation from the switch and the switch may
burn.
Complete soldering within 5 seconds at 350°C or within 3 seconds
at 380°C. If heat is applied for longer period of time, switch characteristics will be deteriorated, e.g., the case will melt and lead wire
insulation will scorch.
Soldering conditions are even more strict for ultra subminiature
switches. Refer to the Precautions for individual models for details.
Quick-Connect Terminals
Use the specified receptacles to connect to quick-connect terminals. Do not apply excessive force horizontally or vertically to the
29
General Information
General Information
terminals, otherwise the terminal may be deformed or the housing
may be damaged.
Wiring Work
When wiring a switch, check the insulation distance between the
switch and the mounting plate. If the insulation distance is insufficient, use an insulation guard or separator. Be particularly careful
when mounting a switch to metal.
Use wire sizes suitable for the applied voltage and carrying current.
Do not wire a switch while power is being supplied.
Using Separators
If providing sufficient insulation distance is a problem or there are
metal components or copper wire near a switch, use a switch with
an insulation guard or use a separator (order separately) to provide
sufficient insulation distance.
Separator for Vj
Separator for SSj
Separator
Separator
Separator for Zj
Separator
Soldering Precautions
When soldering by hand, place the terminal horizontal to the
ground, use a soldering iron with a suitable heat capacity and a suitable amount of solder, and complete soldering quickly. Prevent flux
from entering a switch by exhausting flux gas with an exhaust fan
and by avoiding the contact of the tip of the soldering iron and the
switch body. Flux gas inside a switch may cause contact failure. Do
not apply any force to the terminal or wire immediately after soldering.
Tip of soldering
iron
Incorrect
Correct
When soldering automatically, adjust the amount of solder so that
flux does not float onto the top of PCB. If flux enters the switch, it can
cause contact failure.
30
Operation and Storage Environment
Handling
Do not apply oil, grease, or other lubricants to the sliding parts of a
switch. The intrusion of oil, grease, or other lubricants into the internal part may cause operating failure or contact failure.
Operating Environment
A general switch is not water-resistant. Protect the switch appropriately when using the switch in places with water or oil spray.
Do not use a switch under the condition where vibration or shock is
continuously applied to the switch. If continuous vibration or shock
is applied to a switch, contact failure, malfunction, or decrease in durability may be caused by abrasive powder generated from the internal parts. If excessive vibration or shock is applied to a switch, the
contacts may malfunction, stick, or be damaged.
Mount a switch in the location where vibration and shock is not applied to the switch and in the direction where they do not resonate.
Do not use a switch in the atmosphere of corrosive gas, such as
sulfuric gas (H2S or SO2), ammonium gas (NH3), nitric gas (HNO3),
or chlorine gas (Cl2), or in the atmosphere of high temperature and
humidity. Otherwise, contact failure or corrosion damage may result.
If a switch is used in the atmosphere of silicon gas, arc energy may
attract silicon dioxide (SiO2) to the contacts and contact failure may
result. If there is silicon oil, silicon sealant, a wire covered with silicon, or any other silicon-based product near the switch, attach a
contact protective circuit to suppress the arcing of the switch or eliminate the source of silicon gas generation. Even for a sealed switch,
it may not be possible to prevent all of the gas from penetrating the
seal rubber, and contact failure may result.
Be sure to use a switch at a temperature and humidity within the
specified ranges. If a switch is exposed to radical temperature changes or intense heat, the characteristics of the switch may change.
Separate the switch as far as possible from sources of heat to eliminate the influence.
Storage Environment
When storing a switch, consider countermeasures (e.g., storing in a
plastic bag) to prevent discoloration resulting from sulfidization of
terminals (silver-plated). Make sure that the location is free of corrosive gas or dust with no high temperature or humidity. It is recommended that a switch be inspected before use if it is stored for three
months or more after the production, depending on the location.
General Information
General Information
Switch Trouble and Corrective Action
Type
Failures
related
l t d tto
electrical
characteristics
Location
of failure
Contact
Failure
Contact
f il
failure
Possible cause
Dust and dirt on the contacts.
Water or other liquid has penetrated into a
switch.
Chemical substances have been generated
on the contact surface due to the
atmosphere containing chemical corrosive
gas.
Corrective action
Remove the cause of the p
problem,, p
place
th switch
the
it h in
i a box,
b
or use a sealed
l d
switch.
Use a switch having contacts with high
environmental resistivity (such as gold or
alloy contacts).
Chemical substances have been generated
on the contact surface when the switch
switches a very low load.
Solder flux has penetrated into the switch.
Review the soldering method or use a
sealed or flux-tight switch.
Silicon gas exists near the switch.
Remove the material generating gas, or
adjust contact capacity to prevent
formation of silicon compounds on the
contacts.
Malfunction
The contacts are separated from each other
by vibration or shock.
Use a switch having a high contact force
(generally a high OF).
Contact
welding
The load connected to the switch is too high.
Switch the load with a high-capacity relay
or magnetic relay or insert a contact
protection circuit.
Insulation
degradation
deg
ada o
(b i )
(burning)
Contacts have been melted and scattered
by arc.
Switch the load with a high-capacity relay
or magnetic relay.
Water has penetrated into the switch
because the switch has been used in an
extremely hot environment.
Remove the cause of the problem, place
the switch in a box, or use a sealed
switch.
Liquid has penetrated into the switch and
been carbonized by arc heat.
Failures
related to
mechanical
characteristics
h
t i ti
Actuator
Mounting
section
sec
o
Terminal
Operating
failure
The sliding part of the actuator has been
damaged because an excessive force was
applied on the actuator.
Make sure that no excessive force is
applied to the actuator, or use an auxiliary
actuator mechanically strong.
Foreign material like dust, dirt and oil has
penetrated into the switch.
Remove the cause of the problem or place
the switch in a box.
The actuator does not release because the
operating body is too heavy.
Use a switch having a higher OF.
The switch is loosely installed and thus does
not operate even when the actuator is at the
rated OP.
Secure the switch.
Low
d bilit
durability
The shape of the dog or cam is improper.
Change the design of the dog or cam.
The operating method is improper.
The operating speed is too high.
Review the operating stroke and operating
speed.
Damage
A shock has been applied to the actuator.
Remove the cause of problem or use a
switch mechanically strong.
The caulked part is not good enough or the
assembled condition is poor.
Replace the switch with a new one.
Deformation or drop-out
Actuator was subjected to an excessive
force and force from an inappropriate
direction.
Review the handling and operating
method.
Screws have not been inserted straight.
Check and correct screw insertion
method.
The mounting screws were tightened with
too much torque.
Tighten the screws with an appropriate
torque.
The mounting pitch is wrong.
Correct the pitch.
The switch is not installed on a flat surface.
Install the switch on a flat surface.
An excessive force was applied to the
terminal while being wired.
Do not apply an excessive force.
The plastic part has been deformed by
soldering heat.
Reduce the soldering time or soldering
temperature. (Refer to the information
given under Precautions for that model.)
Damage
Damage
31
