
Single-beam Safety Sensor E3FS 11
Precautions for Correct Use
OMRON's Single-beam Safety Sensor Input
Module (B1 Module) from the F3SX Series is
the only Controller that can be used for the
E3FS-10B4@@@ (type 2). Normal operation may not be
possible if another Single-beam Sensor Controller is
used.
The Sensor cannot be used as part of a safety
system when the mode selection input of the
Single-beam Safety Sensor Receiver is con-
nected to 0 V because the Sensor will turn ON when
light is interrupted (Dark ON). Be sure to connect the
mode selection input to 24 VDC if you want the Sensor
to turn ON when light is received (Light ON).
Safety Distance
The safety distance is the minimum distance that must be
maintained between the Sensor and a hazardous part of the
machine in order to stop the machine before someone or
something reaches it. The safety distance is calculated based
on the following equation when a person moves perpendicular
to the detection zone of the Sensor.
Safety distance (S) = Intrusion speed into the detection zone (K)
x Total response time for the machine and
Sensor
+ Additional distance calculated based on the
detection capability of the Sensor (C)
The safety distance varies with national standards and individ-
ual machine standards. The equation is also different if the di-
rection of intrusion is not perpendicular to the detection zone
of the Sensor. Be sure to refer to related standards.
Here T = T1 + T2 + T3
where
T1 = Maximum machine stop time (s)
T2 = Sensor response time (s)
(From ON to OFF: 2.0 ms for the E3FS)
T3 = F3SX response time (s)
(From ON to OFF: Refer to Response Time.)
The maximum stop time for a machine is the time it takes to
actually stop dangerous parts after the machine receives a
stop signal from the F3SX.
Measure the actual maximum stop time for
the machine and then periodically check it to
see if the time changes.
Reference: Method for Calculating Safety Distance as De-
fined in the European Standard EN999
(with Intrusion Perpendicular to the Detection
Zone)
• K and C are as follows for Single-beam Safety Sensors.
1) When a Single-beam Safety Sensor is used alone (when
the risk assessment indicates that a single optical beam is
sufficient)
K = 1,600 mm/s
C = 1,200 mm
Height of the beam from the ground or from a reference sur-
face: 750 mm (EN999 recommendation)
2) When multiple Single-beam Safety Sensors are installed
at different heights.
K = 1,600 mm/s
C = 850 mm
The beam heights in the following table are the EN999 rec-
ommendations.
Note. Refer to the F3SN/F3SH instruction manuals for details on Safety Light
Curtains and Multi-beam Safety Sensors.
Preventing Mutual Interference
Observe the following items during installation to prevent Sin-
gle-beam Safety Sensors from interfering with each other or
with Safety Light Curtains.
• Leave adequate space between the Sensors during instal-
lation. (Refer to the instruction manuals for the E3FS and
the F3SN/F3SH.)
• Use baffle plates to separate Sensors.
• Alternate Emitters and Receivers during installation. (See
the figure below.)
Check for mutual interference between Single-beam Safety
Sensors or Safety Light Curtains connected to the same or dif-
ferent Control Units before finalizing placement and starting
normal operation.
When installing multiple Safety Light Curtains,
Multi-beam Safety Sensors, and Single-beam
Safety Sensors, take necessary steps to pre-
vent mutual interference. Otherwise detection may fail
and serious injury may result.
Warning
Warning
No. of beams Height from the reference surface
(example: the floor)
2400 mm, 900 mm
3300 mm, 700 mm, 1100 mm
4300 mm, 600 mm, 900 mm, 1200 mm
Warning
Emitter
Receiver
Emitter
Receiver
Receive
Emitter
Receive
Emitter