Advantech TPC-5152T-633AE, Руководство пользователя

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TPC-5000 Series User Manual 16
Step F: Connect the V+ and V- of the power supply to the TPC system.
After completing Steps A to F, power should be supplied to the TPC system.
2.6 Power/Digital Ground and Earth Ground
The purpose of power/digital grounding is to block all external interference to the
chassis and prevent any possibility of a bad grounding design causing electric
shocks. This is known as “Level 1 isolation”, which is not implemented on consumer-
grade PCs.
1. The TPC chassis and earth ground (power pin 3) are short.
2. The TPC chassis and power/digital ground are open.
The TPC system is an industrial-grade product designed to prevent external interfer-
ence and the possibility of electric shocks. To complete the isolation design, the fol-
lowing must be considered:
1. Because the Ethernet is isolated, a LAN connection will not impact the isolation
design.
2. To resolve EMI and ESD issues, general USB devices are designed as a chas-
sis and digital short. However, the TPC system prevents damage to USB
devices. ESD and EMI solutions are designed to use the power ground as a
vent path to ensure that the power ground and chassis ground do not have dif-
ference abnormalities.
3. For COM ports, because there are different COM port designs, long-distance
connections cause voltage differences between the two COM port
chasses.Thus, the cable shell ground must be isolated to the digital ground sig-
nal.
In practical cases, many customers may break the Level 1 isolation with a third-party
device or the cable design. In such situations, we must consider making all grounds
(power, digital, and earth) short and ensure that customers have a good earth ground
connection.
Note! Ensure that all wires follow the installation guidelines or damage to the
system may occur.
If you need to install a device or mini PCIe card, double check the volt-
age of V- and the earth ground. If the voltages are not almost equal with
each other, we recommend shorting V- and the earth ground with wiring.