User`s manual
Base units Overview
8 – 2
8.1.2 Precautions on using the base units Q52B and Q55B
When extension base unit Q52B or Q55B is used, a power of 5 V DC is supplied from the power
supply module on the main base unit through an extension cable.
Observe the following points, when specifying a PLC system with the base units Q52B and
Q55B:
● The power consumption of the modules mounted on the main base unit and on the base
units Q52B and Q55B must not exceed the output current of the main base unit power supply.
● When using the Q52B or Q55B, make sure that the "IN" connector of the Q52B or Q55B is
supplied with 4.75 V DC or higher.
● The Q5B can be used if the voltage drop caused by extension cable is 0.15 V DC or lower.
You can calculate the voltage drop occuring at extension cables by multiplying the extension
cable conductor resistance (refer to section 8.2) with the power consumption of the extension
base unit. Load large current consumption modules on the main base unit.
● For connection of extension base unit Q52B and QQ55B the use of cable Q05B is strongly
recommended.