Mitsubishi Electric MELSEC iQ-F FX5U - Appendix 3 How to Use Analog Inputs Built in CPU Module for Current Inputs

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APPENDIX
Appendix 3 How to use analog inputs built in CPU module for current inputs
Appendix 3 How to use analog inputs built in CPU
module for current inputs
The analog input of the built-in analog can be used as current input (4 to 20 mA DC) for the FX5U CPU module.
Method of using the FX5U CPU module for current inputs (4 to 20 mA DC)
The FX5U CPU module is designed to handle only voltage inputs.
However, the FX5U CPU module can be used for current inputs by connecting a 250  resistor (tolerance: 0.5%) between the
V+ terminal and the V- terminal.
■Example of wiring
*1 Instead of a 250  resistor, a 500  resistor can be connected in parallel. When selecting a resistor, consider the maximum input
current.
*2 For unused channels, short-circuit the "V+" and "V-" terminals.
■Specifications
*1 The digital output value can be changed using the scaling function.
■Example of using the scaling signal
For details of the scaling function, refer to MELSEC iQ-F FX5 User's Manual (Analog Control).
Item Specifications
Analog input 4 to 20 mA DC
Digital output 400 to 2000
*1
Resolution 10 A
Absolute maximum input -2 mA, +60 mA
Default characteristics
(Upper limit value: 4000, lower limit value: 0)
Characteristics converted by the scaling function
(When “upper limit value: 4500, lower limit value: -500” is set)
CH No. goes in  of V+, CH.
CH
33 k
82.7 k
V-
V+
Converting 4 to 20 mA
into 1 to 5 V
250 
*1
*2
2000
Digital output value
Current input
400
0
4 mA 20 mA
2000
Digital output value
Current input
-500
0
4 mA 20 mA