S421

S421 Thermal Mass Flow Sensor for Compressed Air and Gases (Inline-Sensor)

The Inline compressed air flow meter comes with a measuring section in different sizes and fits perfectly in your system.

Affordable inline sensor to measure compressed air flow

Fast response time and high precision

Smartphone app for live readings and easy setup

Seamless integration into the compressed air and gas system

Optional flow conditioner, no need for a straight inlet

No additional temperature and pressure compensation

Isolated 4... 20 mA & Pulse; Modbus/ RTU; Modbus/ TCP; M-Bus

In-line type with measuring section DN15 to DN80

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Flow Range Calculator

The SUTO S421 Inline Thermal Mass Flow Sensor provides reliable compressed air and gas flow and consumption monitoring in main and header lines with a wide measuring range. With the high resolution and sampling rate, a fast and precise measurement is achieved.

Easy Installation and Optional Display

The installation is done through a measuring section with a pre-defined diameter, with R-thread or with flange connections. The flow sensor comes calibrated on the selected measuring section. The optional color display is designed to show all measured values like flow and total consumption on the screen. The display can also be used to manage the sensor settings, like gas types, output signal settings or reference conditions.

Measurement of two gases at the same time

The thermal mass flow sensor can save two calibration curves, this means the sensor can be used in two different gases without any loss of accuracy. This would allow for example compressed air flow to be measured and have the ability to switch to measure Nitrogen by simply changing the gas type via the S4C-FS app or using the sensors display.

Various Sensor Outputs

The S421 Thermal Mass Flow Sensor offers 4 different signal output options. It can have an isolated analog and pulse output to read out the flow and the total consumption. The Modbus/RTU and Modbus/TCP output options offers a state-of-the-art digital interface solution to connect the meter to high level controllers or software solutions. By using M-Bus as an output, the meter can be connected to existing metering networks easily.

Mobile configuration and real-time data

Various settings such as gas type, flow unit and reference standards, can be set ex-factory according to your needs. If settings need to be changed on site, they can be done using the free S4C-FS smart phone application. This enables users to change the settings of the flow sensor wirelessly on site. Flow meter settings are well protected from unwanted access with use of a unique QR access code for each meter.

Should you have any special requests, such as custom flow ranges or different gas types, please contact us here.

Compressed air / gas consumption and flow measurement in main and distribution lines
Compressed air allocation costs within distribution network

MEASUREMENT
Flow
Accuracy	1.5 % of reading ± 0.3 % FS (optional 1 % of reading)
Selectable units	m3/h, m3/min, l/min, l/s, cfm, kg/h, kg/min, kg/s
Repeatability	0.25 % of reading
Sensor	Thermal mass flow sensor
Sampling rate	10 samples / sec
Turndown ratio	200:1
Response time (t90)	0.1 sec
Consumption
Selectable units	m3, ft3, l
Reference conditions
Selectable conditions	20 °C 1000 mbar (ISO1217), 0 °C 1013 mbar (DIN1343) freely adjustable

SIGNAL INTERFACE & SUPPLY
Analog output
Signal	4 ... 20 mA (4-wire), isolated
Scaling	0 ... max flow, freely adjustable
Load	max. 250 Ohm
Update rate	Value updated ever 1 sec
Pulse output
Signal	Switch output, normally open, max. 30 VDC, 20 mA
Scaling	1 pulse per consumption unit (selectable)
Fieldbus
Protocol	Modbus/RTU, Modbus/TCP
Update rate	Value updated ever 1 sec
Supply
Voltage supply	15 ... 30 VDC
Current consumption	max. 200 mA

GENERAL DATA
Configuration
Wireless	S4C-FS App for mobile phones
PC Software	USB Service Kit + Software
Others	Display with 2 touch buttons
Display
Integrated	2.4” color graphic display with 3 touch buttons
Material
Process connection	Stainless steel 1.4404 (SUS 316L)
Housing	PC + ABS
Sensor	Ceramic, glass coated
Metal parts	Stainless steel 1.4404 (SUS 316L)
Miscellaneous
Electrical connection	2 x M12 (5 pole); 1 x M12 (8-pole x-coded) for TCP
Protection class	IP65
Approvals	CE, RoHS, FCC
Process connection	S401: G1/2” (ISO 228/1) S421: Measuring section with R-thread or Flange
Weight	S401: 0.9 kg S421: 0.4 kg (without measuring section)
Operating conditions
Medium	Air, N₂, O₂, CO₂ and other gases
Medium quality	ISO 8573: 4.4.3 or better
Medium temperature	-30 ... +140 °C
Medium humidity	< 90 % rH, no condensation
Operating pressure	max. 5.0 MPa (> 1.6 MPa need installation device)
Ambient temperature	-30 ... +70 °C, -10 ... +50 °C (with display)
Ambient humidity	< 99 % rH
Storage temperature	-30 ... +70 °C
Transport temperature	-30 ... +70 °C
Pipe sizes	S401: ½” ... 12” (bigger pipes on request) S421: ½” ... 3”

Volumetric Flow Ranges
Pipe Specifications			S401			S421
Anschlussgewinde	DN	DI (mm)	S401-S (m3/h)	S401-M (m3/h)	S401-H (m3/h)	Measuring range from to
½”	DN15		-	-		0.5 ... 90 m3/h
¾”	DN20		-	-		0.9 ... 170 m3/h
1”	DN25	27.3	0.5 ... 147.7	0.6 ... 294.7	0.6 ... 356.9	1.5 ... 290 m3/h
1¼”	DN32	36.0	0.9 ... 266.3	1.2 ... 531.5	1.2 ... 643.5	2 ... 500 m3/h
1½”	DN40	41.9	1.2 ... 366.7	1.5 ... 731.9	1.5 ... 886.2	3 ... 700 m3/h
2”	DN50	53.1	2.0 ... 600.1	2.5 ... 1197.6	3.0 ... 1450.0	4 ... 1000 m3/h
2½”	DN65	68.9	3.5 ... 1026.5	5.0 ... 2048.6	5.0 ... 2480.4	6 ... 1500 m3/h
3”	DN80	80.9	5.0 ... 1424.4	7.0 ... 2842.7	7.0 ... 3441.9	8 ... 2500 m3/h
4”	DN100	100.0	10 ... 2183.3	12 ... 4357.2	12.0 ... 5275.7
5”	DN125	125.0	13 ... 3419.6	18 ... 6824.4	18.0 ... 8263.1
6”	DN150	150.0	18 ... 4930.1	25 ... 9838.9	25.0 ... 11913.1
8”	DN200	200.0	26 ... 8785.6	33 ... 17533.3	42.0 ... 21229.5
10”	DN250	250.0	40 ... 13743.9	52 ... 27428.5	60.0 ... 33210.7
12”	DN300	300.0	60 ... 19814.8	80 ... 39544.1	100.0 ... 47880.4