Photoelectric Sensors Technical Guide

General Precautions

For precautions on individual products, refer to Safety Precautions in individual product information.

These Sensors cannot be used in safety devices for

presses or other safety devices used to protect

human life. These Sensors are designed for use in

applications for sensing workpieces and workers

that do not affect safety.

To ensure safety, always observe the following precautions.

● Wiring

● Operating Environment

(1) Do not use a Sensor in an environment where there are explosive or inflammable gases.

(2) Do not use the Sensor in environments where the cables may become immersed in oil or other liquids or where liquids may penetrate the

Sensor. Doing so may result in damage from burning and fire, particularly if the liquid is flammable.

WARNING

Precautions for Safe Use

Item

Typical examples

Power Supply Voltage

Do not use a voltage in

excess of the operating

voltage range.

Applying a voltage in excess

of the operating voltage

range, or applying AC power

(100 VAC or greater) to a DC

Sensor may cause explosion

or burning.

---

Load Short-circuiting

Do not short-circuit the load.

Doing so may cause explo-

sion or burning.

Incorrect Wiring

Do not reverse the power

supply polarity or otherwise

wire incorrectly. Doing so

may cause explosion or

burning.

Connection without a

load

If the power supply is

connected directly without a

load, the internal elements

may burst or burn. Be sure to

insert a load when

connecting the power

supply.

Load

Sensor

Brown

Blue

Black

• DC Three-wire NPN Output Sensors

+

-

(Load

short

circuit)

Load

Sensor

Brown

Blue

Black

• DC Three-wire NPN Output Sensor

(Load short circuit)

Load

Sensor

Brown

Blue

• AC Two-wire Sensors

Example: E3E2

-

+

Load

Sensor

Brown

Blue

Black

• DC Three-wire NPN Output Sensors

Example: Incorrect Polarity

+

-

-

+

Load

Load

Sensor

Brown

Blue

Black

Sensor

Brown

Black

Blue

•

DC Three-wire NPN Output Sensors

Example: Incorrect Polarity Wiring

12 to

24VDC

0V

Sensor

Brown

Blue

Black

• DC Three-wire NPN Output Sensors

Sensor

Brown

Blue

• AC 2-wire Sensors

Example: E3E2 etc.

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