E2KC25MY1 Datasheet, PDF (15/18 Pages) Omron Electronics LLC – Adjustable Long-distance Sensor

Proximity Sensors Technical Guide
●Wiring Considerations
AND/OR Connections for Proximity Sensors
Model
Type of
connection
Connection
AND (series
connection)
DC 2-Wire
OR (parallel
connection)
+
-
+
-
+
-
+
Load
Load
Load
Description
Keep the number of connected Sensors (N) within the range of the following
equation.
VS - N × VR ≥ Operating load voltage
N : Number of Sensors that can be connected
Vs
VR: Residual output voltage of Proximity Sensor
VS: Power voltage
It is possible, however, that the indicators may not light correctly and error
pulses (of approximately 1 ms) may be generated because the rated power
supply voltage and current are not supplied to individual Proximity Sensors.
Verify that this is not a problem before operation.
Keep the number of connected Sensors (N) within the range of the following
equation.
Vs
N × i ≤ Load reset current
N: Number of Sensors that can be connected
i: Leakage current of Proximity Sensor
Example: When an MY (24-VDC) Relay is used as the load, the maximum number
of Sensors that can be connected is 4.
<TL-NY, TL-MY, E2K-@MY@, TL-T@Y>
The above Proximity Sensors cannot be used in a sereis connection. If need-
ed, connect through relays.
VS
AND (series
connection)
<E2E-X@Y>
X1
X2 ^Load
For the above Proximity Sensors, the voltage VL that can be applied to the
X1
VS
load when ON is VL = VS - (Output residual voltage × Number of Sensors), for
both 100 VAC and 200 VAC.
X2
The load will not operate unless VL is higher than the load operating voltage.
This must be verified before use.
Load
When using two or more Sensors in series with an AND circuit, the limit is three
Sensors. (Be careful of the VS value in the diagram at left.)
VL
VS
VS ≥ 100V
AC 2-wire
In general it is not possible to use two or more Proximity Sensors in parallel
with an OR circuit.
(A)
(B)
Load
A parallel connection can be used if A and B will not be operated simulta-
neously and there is no need to hold the load. The leakage current, however,
will be n times the value for each Sensor and reset failures will frequently oc-
cur.
("n" is the number of Proximity Sensors.)
OR (parallel
connection)
(A)
X1
X2 ^Load
(B)
X1 X2
If A and B will be operated simultaneously and the load is held, a parallel con-
nection is not possible.
If A and B operate simultaneously and the load is held, the voltages of both A
and B will fall to about 10 V when A turns ON, and the load current will flow
through A causing random operation. When the sensing object approaches B,
the voltage of both terminals of B is too low at 10 V and the switching element
of B will not operate. When A turns OFF again, the voltages of both A and B
rise to the power supply voltage and B is finally able to turn ON.
During this period, there are times when A and B both turn OFF (approximately
10 ms) and the loads are momentarily restored. In cases where the load is to
be held in this way, use a relay as shown in the diagram at left.
Note: When AND/OR connections are used with Proximity Sensors, the effects of erroneous pulses or leakage current may prevent use. Verify that there are no
problems before use.
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