Yaskawa YASNAC PC NC Connecting Manual - Manual (Page 144)

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YASNAC PCNC Connecting Manual Chapter 10: Connection of General Purpose I/O
10.3.3 Power Supply for I/O Signal
(1) Power Supply Unit Capacity Restriction
The +24V power supply for I/O, external power should be supplied by the machine tool
builder.
Use of power supply unit is possible, but current capacity is restricted by the number of
I/O ON points, therefore, calculate the load current by the number of I/O points and make
sure it is within the allowable limit value.
+24V power supply unit current capacity: 2.5A
(a) Power On unit current consumption (when using power supply unit): 100mA
(b) Panel I/O JANCD-JSP02/JSP04 current consumption (when using power supply unit):
Input current (1 point) : 5.1 mA (at ON)
Output current (1 point) : Varies with load, but up to 60mA
(c) General-purpose I/O signal I/O module (JANCD-FC810/FC860/FC861)
Input current (1 point) : 10.2 mA (at ON)
Calculation example:
When all I/O points ON at JANCD-JSP02/JSP04 LED load (2.7k
Ω
)
51 mA x 64 = 326.4 mA (JANCD-JSP02/JSP04 input current consumption)
24 V/2.7 K x 56 = 497.8 mA (JANCD-JSP02/JSP04 output current consumption)
2500 mA - 326 mA - 498 mA - 100mA = 1576 mA (feedable capacity)
In this status, if power is supplied to JANCD-FC810 from the power supply unit, over
154
inputs are ON, so overcurrent alarm of the power supply unit results.
1576 mA / 10.2 mA = 154 inputs
(2) External Power Supply Specifications
Voltage 24VDC + 5%
Ripple 10%(9P-P)
Use power supply with overcurrent detection function.