19.
19 -
8
LOADING AND INSTALLATION
19.3 Calculation of Heat Generated by the PLC
The operating ambient temperature in the panel where the PLC is stored must be kept
55
or less.For heat dissipation design of the panel, it is necessary to know the average
power consumption (heat generation) of the devices and machinery stored inside.In this
section, a method to obtain the average power consumption of the PLC system is
explained.
Calculate the temperature rise inside the panel from the power consumption.
The power consuming parts of the PLC may be roughly classified into the following blocks:
(1) Power consumption by power supply module
The power conversion efficiency of the power supply module is about 70%, and 30%
is consumed as heat generated, thus, 3/7 of the output power is the power
consumption.Therefore, the calculation formula is:
(2) Total power consumption of 5VDC logic circuits of modules
The 5VDC output circuit power of the power supply module is regarded as the power
consumption of each module.
W
5V
=I
5V
5 (W)
I
5V
: Current consumption of 5VDC logic ladder circuit of each module
I
15V
: Current consumption of 15VDC external power supply part of special function
module
I
24V
: Average current consumption of 24VDC power supply for output module's
internal consumption
(Current consumption equivalent to the points simultaneously ON)
...... Not applicable to a system where 24VDC is supplied externally and a
power supply module with no 24VDC output is used.
Average Power Consumption
Wpw= {(I
5V
5)+(I
15V
15)+(I
24V
24)} (W)
7
3
Summary of Contents for Q2ACPU
Page 1: ......
Page 2: ......
Page 221: ...12 12 12 OVERVIEW OF PROCESSING PERFORMED BY THE QnACPU ...
Page 222: ...12 13 12 OVERVIEW OF PROCESSING PERFORMED BY THE QnACPU ...
Page 237: ...12 28 12 OVERVIEW OF PROCESSING PERFORMED BY THE QnACPU MEMO ...
Page 271: ...16 13 16 POWER SUPPLY MODULE 4 Names and description of parts of the A66P ...
Page 343: ...21 21 13 MAINTENANCE AND INSPECTION 21 4 2 Replacement of the fuse for an output module ...
Page 357: ...22 12 22 TROUBLESHOOTING ...
Page 359: ...22 14 22 TROUBLESHOOTING MEMO ...
Page 429: ...App 32 APPENDICES Trigonometric function Classification Symbol Description ...
Page 537: ...App 140 APPENDICES REMARK 1 Message 1 An error code is displayed in 2 Alert 1 3 Alert 2 ...
Page 539: ...App 142 APPENDICES 2 Q2ACPU Q2ACPU S1 modules Unit mm inch ...
Page 541: ...App 144 APPENDICES 2 A66P power supply module Unit mm inch ...
Page 543: ...App 146 APPENDICES 3 A35B base unit 4 A38B A38HB A38HBEU base unit Unit mm inch Unit mm inch ...
Page 567: ...MEMO ...
Page 569: ......
Page 570: ......