MITSUBISHI ELECTRIC QA6ADP - Manual (Page 18)

17
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
I2
IA
IA
R1 V1
R2 V2
R3 V3
First extension stage
Second extension stage
Third extension stage
Main base unit
Extension base unit (QA6 B)
Extension base unit (A5 B)
Extension base unit (A6 B)
Power
supply
module
Power
supply
module
Power
supply
module
I3
I1
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 5VDC current consumption in the first to third stages *1
IA Current consumption of the QA6ADP
*1: Since the current consumptions I1 to I3 vary depending on modules to be
mounted, refer to the manual for the module to be mounted.
V V1 V2 V3 R1 ( I2 IA 2 ) R2 ( I2 IA 2 ) R3 IA
[Calculating formula]
The minimum value of the 5VDC output voltage of the power supply module
mounted on the main base unit is set to 4.90VDC. Therefore, the voltage of the
IN side connector of the QA6ADP+A5 B/A6 B in the final stage is 4.75VDC or
more only when the sum (V) of voltage drop is 0.15V or less.