Installation
Operating Instructions ET-xx6-A
R. STAHL HMI Systems GmbH / OI_ET_xx6_A_en_V_03_00_36.docx / 03.05.2021
Page 29 of 60
The following versions are possible:
1. If a USB device that is not connected to the mains is connected, voltage can be supplied
from the internal power supply (terminal 1).
2. If a USB device that is connected to the mains is connected, the internal power supply
(terminal 1) must not be connected. The power must be supplied from an external device.
11.4.2.2
Connection terminal with protection type "e" (IEC/EN 60079-7)
The X5 and X7 connection terminals have protection type "e".
Flexible cables with a cross section of 0.2
– 2.5 mm² (AWG24 - AWG14) can be used.
The maximum cable length for the connection with the Ex e USB interfaces (X5 and X7) is
2.5 m [8.2 ft].
The insulation of the wire must reach right up to the terminal body.
11.4.2.2.1 Type 1 connection version
The USB device does not require an external power supply as it uses less than 500 mA.
No connection to the mains via other interfaces, e.g. WLAN stick.
Type 1 connection diagram (e.g. WLAN stick)
11.4.2.2.2 Type 2 connection version
The USB device does require an external power supply to function because it uses over
500 mA (e.g. hard disks, CD / DVD drives).
The USB device is connected to the mains via other interfaces (e.g. USB / serial converter).
Type 2 connection diagram (e.g. hard disk, CD / DVD with power supply)
