Siemens SIMATIC 627B, Руководство по эксплуатации

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SIMATIC Box PC 627B
Operating Instructions, 06/2008, A5E00927393-02
39
Connecting
6
6.1 Connecting peripherals
Note before connecting
NOTICE
Connect only peripheral devices approved for industrial applications to EN 61000-6-2:2005.
Note
Hot-plug peripheral devices (USB) may be connected while the PC is in operation.
CAUTION
Peripheral devices that are incapable of hot-plugging may only be connected after the
device has been disconnected from the power supply.
CAUTION
Strictly adhere to the specifications in the manuals for the peripheral devices.
NOTICE
The connected or built-in peripherals should not introduce a negative field voltage into the
device.
A negative field voltage greater than 0.5 V to ground on the + 3.3 VDC / + 5 VDC / + 12
VDC power rail due to a connected or integrated component can prevent normal operation
or even destroy the computer.
When measuring the negative field voltage, remember the following:
•
The computer must be switched off and the power cable should be plugged in.
• During the measurement, all cables from the plant to the computer should be
connected.
•
All other components in the plant must be active.