Specs Clamp-On Flow Sensor FD-EC series

Amplifier Units







Cable Type

M12 connector type*5

Zero Line Type*6

No. of control outputs



No. of analogue outputs


No. of external inputs


Power supply cable

2-m strand wire, 6-core

100-mm pigtail, M12 terminal, 6 of 8 pins used

No cable

Response time (90% response)

50 ms/100 ms/250 ms/1 s/5 s (selectable, default 250 ms)*1


Control output 1, 2

Instantaneous flow/integrated flow/alert output/pulse output
NPN/PNP setting switching, total of 2 outputs: max. 100 mA, residual voltage: max. 2.5 V

Analogue output

Instantaneous flow
4–20 mA/0–20 mA (switchable), load resistance 260 Ω or less

External input

Zero flow adjustment/zero flow origin adjustment/accumulated flow reset
Short-circuit current: 1.5 mA or less

Network compatibility


NU Series

No. of expansion units

8 units for one NU parent unit, 4 units for one
FS-MC8N/P parent unit*6

Protection circuit

Protection against reverse power connection, output overcurrent, output surges, reverse output connection, head cable miswiring

Protection against head cable miswiring

Power supply

Power voltage

24 VDC+20%/−10% (including ripple), Class2/LPS

24 VDC±10% (including ripple), Class2/LPS

Power consumption

1680 mW*3 (excluding load current)

1290 mW (excluding load current)

Environmental resistance

Ambient temperature

-10 to +55°C (no freezing)*4

Relative humidity

35–85% RH (no condensation)

Vibration resistance

10 to 500 Hz; Power spectral density: 0.816 G2/Hz; X, Y and Z directions

Shock resistance

100 m/s2, 16 ms pulses, 1000 times each for X, Y, and Z directions


Main unit: Polycarbonate, FG terminals: copper/iron


Approx. 90 g

Approx. 42 g

Approx. 26 g

*1 Analogue output response time is 5 ms additional and 63% response.
*2 IO-Link: SpecificationV1.1/COM3 (230.4 kbps) is supported.
*3 Less than 182 mA including load.
*4 The operating ambient temperatures for the adjacent number of cable type/M12 connector type units and the number of zero line type expansion units should be 55°C for 1 to 2 units, 50°C for 3 to 5 units, and 45°C for 6 to 8 units. The prescribed values for the ambient temperature assume that the amplifier unit has been mounted on a DIN rail installed on a metal surface. Exercise special care when installing the product in an airtight space.
*5 Ensure the cable length is 30 m or less (20 m or less when IO-Link is used) for the M12 connector type.
*6 The zero line type should be used by connecting to the FS-MC8N/P and NU Series.
*7 This counts as 2 outputs and 1 input when connecting multiple units to the FS-MC8N/P and NU Series.

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Sensor head










Supported pipe diameter

Pipe outer diameter


1/4” (approx. 6.35 mm)


3/8” (approx. 9.53 mm)



1/2” (approx. 12.7 mm)

Installable range

6.0 ±0.15 mm

6.35 ±0.15 mm

8.0 ±0.15 mm

9.53 ±0.15 mm

10.0 ±0.15 mm

12.0 ±0.15 mm

12.7 ±0.15 mm

Pipe materials

Polyurethane, nylon, PFA*1, others*2

Supported fluids

Air, nitrogen, argon, other gases*3

Supported fluid temperatures

−10 to +60°C

Operating pressure range

0 to 0.75 MPa (upper limit depends on pipe specifications)

Flow detection principle

Transmission time difference method

Rated flow

(volumetric flow)

40 L/min *Initial display

70 L/min *Initial display

100 L/min *Initial display

120 L/min *Initial display

180 L/min *Initial display

200 L/min *Initial display

(at 20°C, atmospheric pressure)

Gas at 20°C, 0.2 MPa

120 L/min

210 L/min

300 L/min

360 L/min

540 L/min

600 L/min

Gas at 20°C, 0.4 MPa

200 L/min

350 L/min

500 L/min

600 L/min

900 L/min

1000 L/min

Gas at 20°C, 0.6 MPa

280 L/min

490 L/min

700 L/min

840 L/min

1260 L/min

1400 L/min


2.5% of F.S. at 250-ms response time*4*5

Display resolution

Instantaneous flow

0.01/0.1/1 L/min

0.1/1 L/min

Integrated flow

0.01/0.1/1/10/100 L

0.1/1/10/100/1000 L

Display method

Output indicators

Environmental resistance

Enclosure rating

IP65 (IEC60529)

Ambient temperature

-10 to +60°C (no freezing)

Relative humidity

35–85% RH (no condensation)

Vibration resistance

10 to 500 Hz; Power spectral density: 0.816 G2/Hz; X, Y and Z directions

Shock resistance

100 m/s2, 16 ms pulses, 1000 times each for X, Y, and Z directions


Sensor unit


Sensor surface

Special rubber


Approx. 102 g

Approx. 105 g

Approx. 114 g

Approx. 115 g

Approx. 116 g

*1 PFA tubing should be used in environments of 40°C or less.
*2 The plastic tube through which ultrasonic waves penetrate.
*3 The gas through which ultrasonic waves penetrate. Readings may become unstable depending on the pipe’s internal pressure and the type of gas.
*4 Accuracy improves with longer response times. As a rule, this is by a proportion of √(250 ms/response time)x.
*5 This is the guaranteed value from verification performed at KEYENCE inspection facilities. Errors may occur according to the type and condition of the customer’s pipes, the type of fluid, the fluid temperature, and other factors.

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