Mitsubishi Electric MELSEC iQ-R Series Configuration Manual page 118

Voltage drop when a MELSEC-Q series extension base unit is used
When the Q5B is used, the Q5B is supplied with 5VDC from the power supply module on the RQ extension base unit, a
voltage drop occurs at extension cables. Incorrect input or output may occur if the specified voltage (4.75VDC or higher) is not
supplied to the IN connector of the Q5B.
When the Q5B is used, check that the IN connector of the Q5B set as the last level is supplied with 4.75VDC or higher.
Connecting the extension base unit to the lower level of the RQ extension base unit with the shortest extension cable is
recommended to reduce the influence of the voltage drop.
The following table lists the conductor resistance value for each extension cable.
Model
QC05B
QC06B
QC12B
QC30B
QC50B
QC100B
The voltage drop can be checked on the engineering tool.
The following window shows the check result.
5 INSTALLATION AND WIRING
116
5.5 Connection Method for the Extension Base Unit
Conductor resistance value for extension cable
0.044
0.051
0.082
0.172
0.273
0.530