*1 Refer to the “Applicable Fluids List” on page 22.
*2 0 L/min is displayed when the flow is less than the zero-cut flow.
*3 When fluids with high temperatures are used, the operating pressure range and proof pressure will be reduced. (For details, refer to the “Operating
Pressure Range” on page 8.)
*4 It is cleared when the power supply is turned OFF. A hold function can be selected. (Intervals of 2 or 5 minutes can be selected.) If 5-minute intervals
are selected, the life of the memory element (electronic parts) is limited to 1 million times. (If energized for 24 hours, life is calculated as 5 minutes x 1
million = 5 million minutes = about 9.5 years.) Therefore, calculate the number of operations and use within the life.
*5 The delay time until the set value reaches 63% in relation to the step input
*6 The delay time until the set value reaches 63% in relation to the step input
There might be a 0.05 s delay at response times of 0.25 s and 0.5 s due to the timing of internal processing.
*7 The stability of the display and analog output can be improved by increasing the response time of the switch output. (For details, refer to the “Stability”
on page 8.)
*8 When options are used, add the weight of the optional parts.
*9 The enclosure refers to the digital flow switch with a lead wire and M12 connector.
*10 This is the flow range in which the product specifications (accuracy, repeatability, etc.) are satisfied. The correct values may not be displayed when
operated outside of the rated flow range.
Specifications (Integrated Display Type)
Model LFE1 LFE2 LFE3
Applicable fluid*1Water, Conductive fluids which do not corrode the fluid contact materials*1
Applicable fluid conductivity*15 μS/cm or more (micro siemens)
Detection method Electrostatic capacity
Rated flow range*10 0.5 to 20 L/min 2.5 to 100 L/min 5 to 200 L/min
Display flow range 0.4 to 24.0 L/min 2.0 to 120.0 L/min 4 to 240 L/min
Set flow range 0.4 to 24.0 L/min 2.0 to 120.0 L/min 4 to 240 L/min
Zero-cut flow*20.4 L/min 2.0 L/min 4 L/min
Smallest settable increment 0.1 L/min 0.5 L/min 1 L/min
Accumulated volume per pulse (Pulse width: 50 ms)
0.1 L/pulse 0.5 L/pulse 1 L/pulse
Operating fluid temperature *30 to 85°C (No freezing or condensation)
Display units Instantaneous flow rate L/min, Accumulated flow L
Repeatability Displayed values: ±2% F.S. Analog output: ±1.5% F.S.
Temperature
characteristics
Ambient temperature ±5% F.S. (25°C reference)
Fluid temperature ±5% F.S. (25°C reference)
Operating pressure range*30 to 1 MPa
Proof pressure*32 MPa
Accumulated flow range*499999999.9 L 999999999 L
by 0.1 L by 1 L
Switch output NPN or PNP open collector output
Maximum load current 80 mA
Maximum applied voltage
28 VDC
Internal voltage drop NPN: 1 V or less (at load current of 80 mA) PNP: 1.5 V or less (at load current of 80 mA)
Response time*5*7Can be selected from 0.25 s, 0.5 s, 1 s, 2 s, or 5 s
Output protection Short-circuit protection
Output mode
Select from hysteresis mode, window comparator mode, accumulated output mode, or accumulated pulse output mode.
Analog output
Response time*6*7Linked with the switch output
Voltage output Output voltage: 1 to 5 V Output impedance: 1 kΩ
Current output Output current: 4 to 20 mA Max. load impedance: 600 Ω
Hysteresis Variable
Display method 2-screen (Main screen: 4-digit, 7-segment, 2-color, Red/Green; Sub screen: 6-digit, 11-segment, White)
Display values updated 5 times per second
Status LED Output 1, Output 2: Orange
Power supply voltage 24 VDC ±10%
Current consumption LFEm: 45 mA or less/LFEmZ: 60 mA or less (Both not including load current)
Environmental
resistance
Enclosure*9IP65
Operating temperature range
0 to 50°C (No freezing or condensation)
Operating humidity range
Operating, Storage: 35 to 85% R.H. (No condensation)
Standards and regulations CE marking (EMC Directive, RoHS Directive)
Fluid contact materials PPS, FKM, Brass
Port size 3/8 (10A) 1/2 (15A) 3/4 (20A) 1 (25A)
Weight (Body)
*8LFEmApprox. 340 g Approx. 400 g Approx. 520 g Approx. 680 g
LFEmZ
For flow switch precautions, refer to the
Operation Manual on the SMC website.
6
3-Color Display Electromagnetic Digital Flow Switch LFE Series
