User Guide

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6F8A0870
(2) Grounding of the LF414 type
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 5.5mm
2
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.)
A G X
B E Y FG
G E
A B X Y
Figure 4.12 Grounding the LF414 Type Detector
A
G
X
B
E
Y FG
G E
A
B
X Y
If the piping material is conductive, connect the
grounding wires to the both ends of the piping flange.
If the piping material is non-conductive, perform grounding
resistance 100 or less.
Grounding terminal
Input signal
cable
Excitation cable
Grounding terminal
Converter
terminal
block
(100 ohm or less
ground resistance)
(100 ohm or less
ground resistance)
Grounding terminal
Input signal
cable
Excitation cable
Converter
terminal
block
Shield twisted
Shield twisted
Grounding terminal
(100 ohm or less
ground resistance)
Shield twisted
Shield twisted
Converter
terminal
block
Converter
terminal
block
Figure 4.11 (a)
Wiring between Detector and Converter (For
grounding the detector, see Figure 4.12 below.)
Figure 4.11 (b)
Wiring between Detector and Converter
(when grounidng of the detector is difficut)
Grounding wire
Grounding
wire
Grounding terminal
Conductive material piping
Example: Metal, etc.
Non-conductive material piping
Example: Resin product or metal piping whose inside is resin lined
Separate
Grounding terminal
(100 ohm or less ground resistance)