User`s manual

18
In case of the above system, use the QA6ADP when the current
consumption of the power supply module mounted on the main base
unit meets the following formula.
6.2 Voltage Drop of Extension Cable
Since 5VDC is supplied to the QA6ADP from the power supply module
mounted on the main base unit, the voltage drop will be caused in the
extension cable.
If the specified voltage (4.75VDC or more) is not supplied to the IN side
connector of the QA6ADP+A5B/A6B, wrong input/output may occur.
When using the QA6ADP, check that the IN side connector of the
QA6ADP+A5B/A6B has 4.75VDC or more.
The following shows an example regarding how to calculate the voltage
drop.
Model
Conductor
resistance value
QC05B 0.044
QC06B 0.051
QC12B 0.082
QC30B 0.172
QC50B 0.273
QC100B 0.530
Symbol Description
V Sum of voltage drop
V1 Voltage drop due to an extension cable between the main base unit and the QA6B
Vn
Voltage drop due to an extension cable between the extension base unit (n-1th
extension stage) and the extension base unit (nth extension stage)
R1
Resistance value of a cable between the main base unit and the extension base unit
QA6B
Rn
Resistance value of an extension cable between the extension base unit (n-1th
extension stage) and the extension base unit (nth extension stage)
I1 to I3 Current consumption (5VDC) at the first to the third extension base units*1
IA Current consumption of the QA6ADP
I > I0 + I2 + I3 + IA 3
[Calculating formula]
I2
IA
IA
R1V1
R2V2
R3V3
First extension
stage
Second extension
stage
Third
extension
stage
Main base unit
Power
supply
module
Power
supply
module
Power
supply
module
I3
I1
IA
I2+IA 2
I2+IA 2
Extension base unit (QA6 B)
Extension base unit (A5 B)
Extension base unit (A6 B)