Fuji Electric Time Delta-C FSV-2 - Remedying a Hardware Fault

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c) There is white noise
all around.
Waveform with the overall noise
d) Pulsed noise is observed.
Waveform with pulsed noise on the signal line
Measurement can be performed if the noise level is smaller than the received waveform level (0.75V
0-p
).
<Cause> <Check>
Noise is placed on the power line. Check the power line using an oscilloscope, and
install a noise-suppression transformer.
Noise is placed on the grounding line (panel earth,
etc).
Check the power line using an oscilloscope, and
remove the ground wire.
Dedicated cable is picking the inductive noise. Move the flow transmitter near the detector and
perform confirmation.
Keep the dedicated cable apart from the power cable.
The distance between the detector and the flow
transmitter is long, and dedicated cable length is long.
Perform grounding according to the figure below.
Insufficient sensitivity
Signal power (AGC_U, AGC_D) 45% or less
Change the detector.
FSSA
→
FSSC
FSSC
→
FSSE
6.5.7. Remedying a hardware fault
If the hardware is found faulty as a result of Section 6.5.1 to Section 6.5.6 above, provide specific details to Fuji Electric.
Flow transmitter
Detector
Ground
Outer shielding of the
dedicated cable is grounded
to the earth.
Ground