SMC Networks CDUJB10-20D, Руководство пользователя

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Series
CUJ
Auto Switch Precautions 1
Be sure to read before handling.
Design and Selection
Warning
1. Confirm the specifications.
Read the specifications carefully and
use this product appropriately. The
product may be damaged or malfunc-
tion if it is used outside the range of
specifications for load current, voltage,
temperature or impact.
2. Take precautions when mul-
tiple cylinders are used
close together.
When multiple auto switch cylinders
are used in close proximity, magnetic
field interference may cause the
switches to malfunction. Maintain a
minimum cylinder separation of 40mm.
(When the allowable separation is
indicated for each cylinder series, use
the specified value.)
3. Monitor the length of time
that a switch is ON at an
intermediate stroke position.
When an auto switch is placed at an
intermediate position of the stroke and
a load is driven at the time the piston
passes, the auto switch will operate,
but if the speed is too great the
operating time will be shortened and
the load may not operate properly. The
maximum detectable piston speed is:
4. Keep wiring as short as
possible.
<Solid state switch>
Although wire length should not affect
switch function, use a wire 100m or
shorter.
5. Be careful of the internal
voltage drop of the switch.
<Solid state switch>
Generally, the internal voltage drop will
be greater with a 2 wire solid state auto
switch than with a reed switch.
• Note that there will be a large voltage
drop if auto switches are connected in
series as shown below. (Refer to
internal voltage drop in the auto switch
specifications.)
[The voltage drop will be "n" times
larger when "n" auto switches are
connected.]
Even though auto switches operate
normally, the load may not operate.
Auto switch operating range (mm)
Load operating time (ms)
V(mm/s) =
x 1000
• Similarly, when operating below a
specified voltage, it is possible that the
load may be ineffective even though
the auto switch function is normal.
Therefore, the formula below should be
satisfied after confirming the minimum
operating voltage of the load.
Also, note that a 12VDC relay is not
applicable.
6. Be careful of leakage current.
<Solid state switch>
With a 2 wire solid state auto switch,
current (leakage current) flows to the
load to operate the internal circuit even
when in the OFF state.
If the above requirement is not
satisfied, it 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.
7. Do not use a load that
generates surge voltage.
<Solid state switch>
Although a zener diode for surge
protection is connected at the output
side of a solid state auto switch,
damage may still occur if the surge is
applied repeatedly. When a load, such
as a relay or solenoid, which generates
surge is directly driven, use a type of
switch having a built-in surge absorbing
element.
8. Cautions for use in an inter-
lock circuit
When an auto switch is used for an
interlock signal requiring high reliability,
devise a double interlock system to
avoid trouble by providing a
mechanical protection function, or by
also using another switch (sensor)
together with the auto switch. Also,
perform periodic maintenance and
confirm proper operation.
9. Ensure sufficient clearance
for maintenance activities.
When designing an application, be
sure to allow sufficient clearance for
maintenance and inspections.
Supply
voltage Internal voltage
drop of switch
> Minimum operating
voltage of load
–
Operating current of load
(OFF condition)
Leakage current
>
Mounting and Adjustment
Warning
1. Do not drop or bump.
Do not drop, bump or apply excessive
impacts (1000m/s
²
or more for solid
state switches) while handling. Al-
though the body of the switch may not
be damaged, the inside of the switch
could be damaged and cause a mal-
function.
2. 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 ele-
ments of the switch to be damaged by
the stress.
3. Mount switches using the
proper tightening torque.
When a switch is tightened beyond the
range of tightening torque, the mount-
ing screws or switch may be damaged.
On the other hand, tightening below the
range of tightening torque may allow
the switch to slip out of position. (Refer
to page 10 regarding switch mounting,
movement and tightening torque, etc.)
19
Load
Warning