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Design and Selection
Caution
Mounting and Adjustment
3. Pay attention to leakage current.
<Solid state switch>
With a 2-wire solid state switch, current (leakage current)
flows to the load to operate the internal circuit even when in
the OFF state.
If the condition given in the above formula is not met, internal
circuit will not reset correctly (stays ON). Use a 3-wire switch if
this specification cannot be satisfied.
Moreover, leakage current flow to the load will be “n” times
larger when “n” auto switches are connected in parallel.
4. Provide enough space for maintenance.
When designing an application, be sure to allow sufficient
clearance for maintenance and inspections.
Mounting and Adjustment
Warning
1. Instruction manual
Install the products and operate them only after reading the in-
struction manual carefully and understanding its contents. Also
keep the manual where it can be referred to as necessary.
2. Do not drop or bump.
Do not drop, bump or apply excessive impacts (300 m/s
2
or
more for reed switches and 1000 m/s
2
or more for solid state
switches) while handling. Although the body of the switch may
not be damaged, the inside of the switch could be damaged
and cause a malfunction.
3. Mount switches using the proper tightening
torque.
When a switch is tightened beyond the range of tightening tor-
que, the mounting screws, or switch may be damaged.
On the other hand, tightening below torque range may allow
the switch to slip out of position. (Refer to switch mounting for
each series regarding switch mounting, moving, and fastening
torque, etc.
4. Mount a switch at the center of the operating
range.
Adjust the mounting position of an auto switch, so that the pis-
ton stops at the center of the operating range (the range in
which a switch is stayed ON). (The mounting positions shown
in the catalog indicate the optimum position at stroke end.) If
mounted at the end of the operating range (around the border-
line of ON and OFF), operation will be unstable.
<D-M9
>
When the D-M9 auto switch is used to replace old series auto
switch, it may not activate depending on operating condition
because of its shorter operating range.
Such as
• Application where the stop position of actuator may vary and
exceed the operating range of the auto switch, for example,
pushing, pressing, clamping operation, etc.
• Application where the auto switch is used for detecting an in-
termediate stop position of the actuator. (In this case the de-
tecting time will be reduced. )
In these applications, set the auto switch to the center of the
required detecting range.
5. Ensure sufficient clearance for maintenance
activities.
When designing an application, be sure to allow sufficient
clearance for maintenance and inspections.
Caution
1. Do not carry a cylinder by the auto switch
lead wires.
Never carry a cylinder by its lead wires. This may not only
cause broken lead wires, but it may cause internal elements of
the switch to be damaged by the stress.
2. Fix the switch with appropriate screw instal-
led on the switch body. If using other
screws, switch may be damaged.
Wiring
Warning
1. Confirm proper insulation of wiring.
Be certain that there is no faulty wiring insulation (such as
contact with other circuits, ground fault, improper insulation
between terminals, etc.). Damage may occur due to excess
current flow into a switch.
2. Do not wire in conjunction 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.
Caution
1. Avoid repeatedly bending or stretching lead
wires.
Broken lead wires will result from repeatedly applying bending
stress or stretching force to the lead wires.
2. Be sure to connect the load before power is
applied.
<2-wire type>
If the power is turned ON when an auto switch is not connec-
ted to a load, the switch will be instantly damaged because of
excess current.
3. Do not allow short circuit of loads.
<Reed switch>
If the power is turned ON with a load in a short-circuited condi-
tion, the switch will be instantly damaged because of excess
current flow into the switch.
<Solid state switch>
The switches do not have built-in short circuit protection cir-
cuits. If loads are short circuited, the switches will be instantly
damaged, as in the case of reed switches.
Take special care to avoid reverse wiring with the brown
power supply line and the black output line on 3-wire type
switches.
Series
MY3
Auto Switch Precautions 2
Be sure to read this before handling.
>
Current to operate load
(Input OFF signal of controller)
Leakage
current
Warning
MY3A3B.qxd 06.2.17 9:13 AM Page 46
