Calculation For The Current Consumption Value Of A Usb Device - Mitsubishi Electric MELSEC iQ-R Series User Manual

Calculation for the current consumption value of a USB device

Depending on a device connected to a USB port of this product, the upper limit of the current consumption value of this
product (threshold value of a current consumption error (USB port forced stop)) may be exceeded. When connecting a
peripheral device, ensure that it is used within a range that does not exceed the threshold value of a current consumption
error (warning). (Page 211 Current Consumption Monitoring Function)
If the threshold value of a current consumption error (USB port forced stop) is exceeded, this product stops the supply of
current and communication to a USB port.
Term
Current consumption value
Threshold value of a current consumption error (USB port
forced stop)
Threshold value of a current consumption error (warning)
If the supply of current to a USB device increases, the current consumption value of a module may exceed the threshold value
of a current consumption error (USB port forced stop). Construct a system so that the current consumption value of the
module is equal to or below the threshold value of a current consumption error (warning).
Current consumption
4.35A
Excess from the threshold value
4.17A
Current that can be supplied to
1.0A*¹
peripheral devices from USB ports
Current consumption of this
3.17A*²
0A
*1 The current value that can be supplied to a peripheral device from a USB port varies according to the current consumption of this
product.
*2 The current value when the maximum load is on this product. It may be 3.17 A or lower depending on the connection of an SD memory
card and CFast card or the CPU load status.
As examples, the following peripheral devices consume large current:
• USB-connected camera
• External DVD drive
• Portable HDD
6 SYSTEM CONFIGURATION
60
6.1 Hardware Configuration
Description
A total of the current consumption value of the SD memory card and CFast cards (primary and
secondary) of this product and the one supplied to peripheral devices from the USB ports
A threshold value (4.35 A) to stop the communication and the supply of current to a USB port
A threshold value (4.17 A) to notify that the margin between the current consumption value
and the threshold value of a current consumption error (USB forced stop) is reduced
Current consumption error
(USB port forced stop)
Current consumption error
(warning)
product