HMIs, human machine interfaces ► ET-208 ► Electrical Installation ET-208 ► Connection of ► External USB devices ► Connection in hazardous area ► Connection to non-live devices
An external USB device can be connected at terminal X4.
The USB device has to meet the requirements for connection to an Ex(e) interface and must be mounted inside an explosion-protected enclosure.
•The USB device does NOT require an external power supply as it uses less 500 mA.
•No connection to the mains via other interfaces.
HMI USB Ex(e) connector
e. g. Ex d housing
USB - device *2
USB cable twisted data wires
Terminals USB(e) device
No connection to mains
Data cable wires must be twisted right up to terminal.
e. g. WLAN stick.
X4 - USB(e)
External USB devices