1. Confirm the specifications.
Read the specifications carefully and use this product appro-
priately. The product may be damaged or malfunction if it is
used outside the specification range for load current, voltage,
temperature or impact, etc.
2. Cautions for use in an interlock circuit
When a magnetic field resistant 2-color display solid state
auto switch is used for an interlock signal requiring high reli-
ability, provide a mechanical function or device a double inter-
lock system by using another switch (sensor) together with the
auto switch to avoid trouble.
Also, perform periodic maintenance and confirm proper opera-
tion.
Design / Selection
Warning
1. Do not use a load that generates surge volt-
age.
Although a surge protection varistor is connected to the output
of the magnetic field resistance 2-color display solid state auto
switch, it may be damaged if surge is repeatedly applied.
When loads such as relay or solenoid valves that generate
surge are directly operated, use loads that incorporate a surge
absorption element.
2.
Take precautions when multiple cylin-
ders/actuators are used close together.
When multiple magnetic field resistant 2-color display solid
state auto switch cylinders/actuators are used in close proxim-
ity, magnetic field interference may cause the auto switches to
malfunction. Maintain a minimum cylinder separation of 40
mm. (When the allowable interval is specified for each cylin-
der series, use the indicated value.)
The auto switches may malfunction due to the interference
from the magnetic fields.
3. Pay attention to the internal voltage drop of
the auto switch.
Generally, the internal voltage drop will be greater with a 2-
wire solid state auto switch than with a reed auto switch. Take
note that a 12 VDC relay is not applicable.
• In the same way, when operating under a specified voltage,
although an auto switch may operate normally, the load may
not operate. Therefore, the formula below should be
satisfied after confirming the minimum operating voltage of
the load.
4. Pay attention to leakage current.
<Solid state/2-wire type>
Current (leakage current) flows to the load to operate the in-
ternal circuit even when in the OFF state.
If the criteria given in the above formula are not met, it will not
reset correctly (stays ON).
Moreover, leakage current flow to the load will be “n” times
larger when “n” auto switches are connected in parallel.
5. Ensure sufficient clearance for maintenance
activities.
When designing an application, be certain to allow sufficient
clearance for maintenance.
Caution
1. Confirm proper insulation of wiring.
Be certain that there is no faulty wiring insulation (contact with
other circuits, ground fault, improper insulation between termi-
nals, etc.). Damage may occur due to excess current flow into
a switch.
2. Do not wire with power lines or high voltage
lines.
Wire separately from power lines or high voltage lines, avoid-
ing parallel wiring or wiring in the same conduit with these
lines. Control circuits containing auto switches may malfunc-
tion due to noise from these other lines.
3. Avoid repeatedly bending or stretching lead
wires.
Broken lead wires will result from repeatedly applying bending
stress or stretching force to the lead wires.
4. Do not allow the load to be short circuited.
A protective circuit shuts off the output when overcurrent flows
due to load short circuit, etc. In that case, shut off the power
supply and eliminate the cause of the overcurrent. Then, ap-
ply the power supply again.
Wiring
Caution
Mounting / Adjustment
Caution
1. Do not drop or bump.
Do not drop, bump or apply excessive impacts (1000 m/s
2
or
more) while handling. Although the body of the auto switch may
not be damaged, the inside of the auto switch could be dam-
aged and cause malfunction.
2. Observe the proper tightening torque for
mounting an auto switch.
When an auto switch is tightened beyond the range of tighten-
ing torque, auto switch mounting screws, auto switch mounting
brackets or auto switch may be damaged.
On the other hand, tightening below the range of tightening tor-
que may allow the auto switch to slip out of position.
3. Do not carry a cylinder/actuator by the auto
switch lead wires.
Never carry a cylinder/actuator by its lead wires. This may not
only cause broken lead wires, but it may cause internal ele-
ments of the auto switch to be damaged by the stress.
Magnetic Field Resistant 2-Color Display Solid State Auto Switch
Specific Product Precautions 1
Be sure to read this before handling. Refer to back pages 1 and 2 for Safety Instructions,
“Handling Precautions for SMC Products” (M-E03-3) for Auto Switches Precautions.
Supply
voltage
–
>
Internal voltage
drop of auto switch
Minimum operating
voltage of load
>
Operating current of load (OFF condition)
Leakage current
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