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INF-TN1FSH-E
3.3. Flow transmitter wiring
3.3.1. Cautions in wiring
CAUTION
(1) Use a dedicated cable (FLY) as a signal cable between the detector (FSW) and the flow transmitter
(FSH). Do not join cable in the middle.
(2) Be sure to let the signal cables installed between the detector and the flow transmitter run through a
metal conduit tube. The signal cables for upper and the lower streams can be made to run through
the conduit tube together. However, do not let the power cable run through the conduit tube
together with the signal cables to avoid induction problems.
(3) Use shielded cables for output signals as far as possible.
(4) To prevent noise from coming in, avoid installing wiring in a duct together with the power cable.
(5) Directly ground the power cable that includes a ground lead.
(6) The flowmeter is not equipped with a power switch. Mount one separately.
(7) Tightly seal the unused wiring ports with supplied sealing caps.
3.3.2. Applicable wires
Use the following cables.
•
Power
cable:
3-wire or 2-wire cabtyre cable
Nominal sectional area: 0.75 mm
2
or more
Finished outer diameter:
φ
11 mm
•
Output
signal
cable:
2-wire or multi-wire cabtyre cable as required
Finished outer diameter:
φ
11 mm
•
Cable between detector and flow transmitter:
Cable for ultrasonic wave signals (High-frequency coaxial double shield cable with characteristic impedance
of 50
Ω
, With waterproof BNC connector provided on one side)
Finished outer diameter:
φ
7.3 mm
Cable for temperature sensor (3-wire shielded cable, With waterproof connector provided on one side)
Finished outer diameter:
φ
6.9 mm
3.3.3. Treatment of wiring port
The casing of the flow transmitter is of watertight type (IP67). However, to prevent entry of moisture and occurrence
of condensation, airtight processing of wiring ports is required. Be sure to take measures against entry of water using
the waterproof glands supplied with the instrument. Tightly seal unused glands using the supplied sealing caps.
CAUTION
Do not install the flow transmitter in a place subject to the occurrence of flooding.