Alicat liquid meters and controllers route the fluid through a laminar flow element (LFE). Two pressure taps measure the differential pressure across the LFE; with a known geometry (and the Poiseuille relationship), the instrument calculates volumetric flow. A temperature sensor stabilises readings, and an optional gauge pressure sensor displays line pressure. Because liquids are (effectively) incompressible, volumetric flow is the right quantity to report—no gas law compensation is required. The architecture has no heated elements and no moving parts, delivering instant on behaviour and very fast response.
Key technology advantages
- Fast dynamics: measurement updates in ~10–20 ms on meters; control response from ~30–100 ms on controllers (model and setup dependent).
- Multi parameter display in real time: volumetric flow, fluid temperature and (optionally) line pressure on the front panel.
- Low pressure drop designs and quick de aeration via front bleed ports improve commissioning and accuracy.
Overview: Alicat L / LB / LC / LCR liquid series
L Series — Fixed liquid flow meters (volumetric)
- Use case: inline monitoring and verification of liquid flow with local display.
- Ranges: 0.5 ccm to 10 L/min full scale.
- Accuracy: ±2% of full scale; 50:1 turndown; ~20 ms indication response.
- Signals: Analogue (0–5 V, 1–5 V, 0–10 V, 4–20 mA) plus RS 232 (others optional).
- Options: pressure readout, hazardous area ratings, corrosion resistant LS variants.
LB Series — Portable, battery powered liquid meters
- Use case: handheld flow verification around the lab or onsite.
- Ranges: 0.5 ccm to 10 L/min full scale.
- Battery: up to ~14–18 hours per charge (display dependent).
- Comms: USB serial by default; Bluetooth® optional on current models.
LC Series — Low flow controllers (valved)
- Use case: closed loop control and precision dosing at low flows.
- Ranges: typically 5 ccm to 500 ccm full scale (controller), ±2% FS, ~100 ms typical control response; PID valve tuning accessible.
- Signals & protocols: analogue + RS 232/RS 485/Modbus; industrial buses (e.g., EtherNet/IP, EtherCAT, PROFIBUS) available.
- Features: front bleed screws to remove air; optional pressure sensor.
LCR Series — Higher flow controllers
- Use case: rapid liquid control and dispensing at higher rates.
- Ranges: typically 1 to 10 L/min full scale; ±2% FS; fast ~100 ms typical control response.
- Benefits: custom orifice sizing for your duty; same display/comms/bleed port conveniences as LC.
Features & benefits
- Instant on: accurate in <1 second, ideal for intermittent or mobile use. (L, LB, LC, LCR)
- Multi variable visibility: see flow, temperature and pressure on one screen—fewer instruments to wire, fewer failure points. (L, LB, LC, LCR)
- Precision dispensing: optional firmware/hardware packages support batch dosing with fast valve response and tuneable PID. (LC, LCR)
- Broad range coverage: 50:1 turndown reduces the need for multiple SKUs per line. (All)
- Connectivity that fits your plant: analogue I/O, serial ASCII/Modbus as standard, with EtherNet/IP, EtherCAT, PROFIBUS/PROFINET as options for PLC integration. (All)
- Hazardous area options: ATEX/CSA (e.g., Ex nA IIC, T4) available for Zone 2/Class I Div 2. (L, LC, LCR)
- Calibration & assurance: supplied with NIST traceable calibration and backed by a limited lifetime warranty. (All)
- Portable verification: LB gives you quick checks and validation anywhere without cabling—handy for commissioning and service teams. (LB)
- Ultra fast to stable: meters indicate within ~10–20 ms; controllers settle quickly (as fast as ~30–100 ms), cutting cycle times on dosing and batching. (L, LC, LCR)
Posted by James Kybird, Managing Director
Published: 6th July 2026
Page updated: 6th July 2026
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