5 Input Specifications and Wiring Methods
XC series PLC input power is from its interior 24V power, if the exterior power drives
photo-electricity sensor etc., this exterior power should be DC24V±4V. Please use NPN open
collector type for sensor output transistor
External circuit used by
sensors
2
Input Wiring
3
Input terminal
When connect input terminal and COM terminal with contacts without voltage or
NPN open collector transistor, if input is ON
，
LED lamp lights, which indicates input
。
There are many COM terminals to connect in PLC.
Input circuit
Use optical coupling instrument to insulate the input once circuit and twice circuit
，
There’s a C-R filter in the twice circuit
。
It is set to avoid wrong operation caused by
vibration of input contacts or noise along with input signal. As the preceding reason, for
the changing of input ON
→
OFF
，
OFF
→
ON
，
in PLC, the response time delays about
10ms
。
There’s a digital filter inside X000~X015
。
This kind of filter can vary from
0~15ms according to the special register (FD8000).
Input sensitive
The PLC’s input current is DC24V 7mA, but to be safe
，
it needs current up to 3.5mA
when it’s ON
，
lower than 1.5mA when it’s OFF.
