Emerson FB3000, Инструкция по эксплуатации

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Emerson FB3000 RTU Instruction Manual
D301851X012
May 2022
Installation 11
Use twisted pair, shielded and insulated cable for communication and I/O wiring to minimize
signal errors caused by electromagnetic interference (EMI), radio frequency interference (RFI)
and transients. When using shielded cable, ground all shields at a suitable Instrument Earth
connection point. This prevents circulating ground current loops that can cause signal errors.
See the FB3000 product data sheet for information about applicable standards for EMI and RFI
emissions and susceptibility.
CAUTION
To avoid damage to terminal blocks, exercise care when unplugging them. Gently pull up on one
end, then gently pull up on the other end, then continue alternating this way to gradually work
the terminal block out of its socket.
2.5 Grounding
There are four separate and distinct ground references within the FB3000 architecture. The
chassis ground lug (also known as Protective Earth or PE), internal system bus ground, isolated
ground, and the 24V loop ground.
Chassis Ground Lug
The RTU includes a chassis ground lug to the left of the power supply modules. In CSA documents,
this may be called the Protective earthing (PE) conductor. The chassis ground lug provides a path
to earth ground for electrical safety, static discharge, and stray voltage from a lightning strike.
CAUTION
Do not use the chassis ground lug for a direct connection to a lightning arrestor/lightning rod.
The chassis ground lug is completely isolated from the isolated, signal, and loop power ground
terminals on I/O modules, or from the 24V loop power ground terminal on some I/O modules. To
prevent noise and equipment damage, you should keep these grounds separate from the chassis
ground.