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MELSEC-Q 
2   INPUT MODULE SPECIFICATIONS 
2.11 QX42 DC Input Module (Positive Common Type) 
Type 
Specifications 
DC input module (Positive common type) 
QX42 Appearance 
Number of input points  64 points 
 
Isolation method  Photocoupler 
Rated input voltage  24VDC (+20/-15%, ripple ratio within 5%) 
Rated input current  Approx. 4mA 
Input derating  Refer to the derating chart. 
ON voltage/ON current  19V or higher/3mA or higher 
OFF voltage/OFF current  11V or lower/1.7mA or lower 
Input impedance  Approx. 5.6kΩ 
Response 
time 
OFF to ON 
1ms/5ms/10ms/20ms/70ms or less (configured in PLC parameter)  1  
(Default: 10ms) 
ON to OFF 
1ms/5ms/10ms/20ms/70ms or less (configured in PLC parameter)  1  
(Default: 10ms) 
Dielectric withstand voltage  560VAC rms/3 cycles (altitude 2000m) 
Insulation resistance  10MΩ or more by insulation resistance tester 
Noise immunity 
By noise simulator of 500Vp-p noise voltage, 1 s noise width  
and 25 to 60Hz noise frequency 
First transient noise IEC61000-4-4: 1kV 
Protection degree  IP2X 
Common terminal arrangement  32 points/common (common terminal: 1B01, 1B02, 2B01, 2B02) 
Number of occupied I/O points  64 points (I/O assignment is set as a 64-point input module.) 
Operation indicator  ON indication (LED), 32 point switch-over using switch 
External connections  40-pin connector 
Applicable wire size 
0.088 to 0.3mm
2
 (For A6CON1 or A6CON4) 2 
Applicable connector  A6CON1, A6CON2, A6CON3, A6CON4 (optional)  
Applicable connector/terminal block 
converter module 
A6TBXY36, A6TBXY54, A6TBX70 
Internal current consumption 
(5VDC) 
90mA (TYP. all points ON) 
Weight 0.18kg 
 
1:
 
For 
the
 setting method, refer to Section 1.3.1. 
2
: When 
using
 A6CON2 or A6CON3, refer to Chapter 7. 
 
QX42
24VDC
4mA
QX42
DISPLAY
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