507
Analog I/O Units
Section 9-4
Note
(1) Connect the shield to the FG terminal to prevent noise.
(2) When an input is not being used, short the + and
−
terminals.
(3) Separate wiring from power lines (AC power supply lines, high-voltage
lines, etc.)
(4) When there is noise in the power supply line, install a noise filter on the
input section and the power supply terminals.
(5) Refer to the following diagram regarding wiring disconnections when volt-
age input is being used.
For example, if analog input device 2 is outputting 5 V and the same
power supply is being used as shown above, about 1/3, or 1.6 V, will be
applied at the input for input device 1.
Consider the following information on open input circuits when using volt-
age inputs. Either use separate power supplies, or install an isolator at
each input.
If the same power supply is used as shown in the following diagram and
an open circuit occurs at point A or B, an unwanted current flow will occur
as shown by the dotted lines in the diagram, creating a voltage at the
other input of about 1/3 to 1/2. If the 1 to 5 V range is being used, the
open-circuit detection function will not operate. Also, if there is an open
circuit at C, the open-circuit detection function will not operate because
the negative sides are the same.
(6) When external power is supplied (when range codes are set), or when
the power is interrupted, there may be a pulse status analog output of up
to 1 ms. If this status is a problem, take the following measures.
• Turn ON the power to the CP1L-EL/EM CPU Unit, check the operation
status, and then turn ON the power at the load.
• Turn OFF the power to the load and then turn OFF the power to the
CP1L-EL/EM CPU Unit.
A
C
B
Analog
output
device
1
Analog
output
device
2
24 VDC
Summary of Contents for CP1L-EL20DR-D
Page 3: ...CP1L EL20D CP1L EM30D CP1L EM40D CP1L EL EM CPU Unit Operation Manual Produced July 2017...
Page 4: ...iv...
Page 10: ...x...
Page 22: ...xxii...
Page 34: ...xxxiv Software Licenses and Copyrights 7...
Page 192: ...158 Trial Operation and Debugging Section 5 3...
Page 250: ...216 Automatic Clock Adjustment and Specifying Servers by Host Name Section 6 7...
Page 666: ...632 Trouble Shooting Section 11 7...
Page 696: ...662 Standard Models Appendix A...
Page 805: ...771 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 806: ...772 Connections to Serial Communications Option Boards Appendix F...
Page 836: ...802 PLC Setup Appendix G...
Page 838: ...804 TCP Status Transitions Appendix H...
Page 840: ...806 Ethernet Network Parameters Appendix I...
Page 842: ...808 Buffer Configuration CP1L EL EM Appendix J...
Page 844: ...810 Ethernet Specifications Appendix K...
Page 851: ...Index 817 work words 118 write protection 447...
Page 852: ...818 Index...
Page 854: ...820 Revision History...
Page 855: ......