6F3B0253
3.I/O Application Precautions
3.1Application precautions for input signals
| ! WARNING | Configure emergency stop and safety interlocking circuits outside the |
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(1)Minimum ON/OFF time of the input signal
The following conditions guarantee correct reading of the ON/OFF state of the input signal:
Input ON time: ON delay time + the time for one scan
Input OFF time: OFF delay time + the time for one scan
The ON and OFF times of the input signals must be longer than these intervals.
(2)Increasing the contact current
The reliability of some contacts cannot be guaranteed by the specified input current. In this case, install an external bleeder resistor to increase the contact current.
V
| Bleeder resistor | |
I | I1 | T1 |
R |
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| I2 | circuit |
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R = | V |
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I − I 1 |
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Wattage > | V 2 | ⋅ 3 | |||
R | |||||
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(3)Connecting transistor output device
An example of connecting a transistor output device to
•For NPN open collector
T1 input
C circuit
•For PNP open collector
C
T1 input circuit
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