Toshiba manual Grounding of the LF414 type, － ３３ －, ６Ｆ８Ａ０８７０

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(2) Grounding of the LF414 type

Separate

Ground the external grounding terminal of the detector and the FG terminal of the converter (or external grounding terminal of the converter) securely (grounding resistance 100Ω or lower). Use grounding wire material of IV wire 5.5mm2 or more. Do not share a grounding wire with other instruments where grounding current may flow. (An independent grounding is preferable.)

If it is difficult to perform grounding work at the detector side because of a pit installation or other reasons, use a 3-core cable for the excitation cable and connect the E terminal of the detector to the E terminal of the converter. (The E terminal of the converter is internally connected with the FG terminal and the converter case.)

Converter A		G		X
terminal	B	E		Y	FG
block
Shield twisted
					Grounding terminal
Input signal					(100 ohm or less
					ground resistance)
cable
					Excitation cable
Shield twisted					Grounding terminal
		G		E	Converter
	A	B	X	Y	terminal
					block

(100 ohm or less

Figure 4.11 (a) ground resistance)

Wiring between Detector and Converter (For grounding the detector, see Figure 4.12 below.)

Converter	A	G	X
terminal	B	E	Y	FG
block

Shield twisted

Grounding terminal

(100 ohm or less

ground resistance)

Input signal
cable	Excitation cable

Shield twisted

Grounding terminal

G			E		Converter
					terminal
A	B	X		Y	block

Figure 4.11 (b)

Wiring between Detector and Converter (when grounidng of the detector is difficut)

Conductive material piping Example: Metal, etc.

Non-conductive material piping

Example: Resin product or metal piping whose inside is resin lined

Grounding terminal

Grounding

wire

•If the piping material is conductive, connect the grounding wires to the both ends of the piping flange.

Grounding terminal

Grounding wire

(100 ohm or less ground resistance)

•If the piping material is non-conductive, perform grounding resistance 100Ω or less.

Figure 4.12 Grounding the LF414 Type Detector

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