Field Intelligent Device Series
Electromagnetic Flowmeter
Introduction
The electromagnetic flowmeter uses Faraday's Law of
electromagnetic induction to measure the process flow.
The device consists of two units: a detector, through
which the fluid to be measured flows and in which
low-level signals proportional to flow rates are obtained;
and a converter, which supplies excitation current to the
detector, and amplifies the signals from the detector and
then processes and converts the signals into the 4–20
mA dc current signal. The LF470 is a small meter size
detector designed to measure a small amount of fluids
containing substances such as chemicals.
The wetted materials for the LF470 are corrosion
resistant ceramic and platinum electrods and are
applicable to almost any kind of fluids. The LF470 is a
lightweight
palm-sized
multi-functional converter LF612 (separate type) and
1
LF232*
(separate type) equipped with its patented
Noise-Sentry original noise-suppression circuit and
advanced algorithms. The LF470 is highly resistant to
noise and provides a stable output even for fluids
containing slurries. IR (Infrared) switches enable
parameter setting of the converter without removing the
cover. Flow direction can be set in either way, and its
unique 128 x 128 dot matrix LCD display allows the
LCD to be rotated electronically to be rotated to 90, 180
and 270 degrees without opening the cover
The AF900 hand-held terminal (HART*
can be used to communicate with the flowmeter from a
remote place. PROFIBUS-PA*
as an option.
*1: Please refer to the document "TIC-LF232".
*2: HART protocol (Highway Addressable Remote
Transducer) is a communication protocol for industrial
sensors recommended by the HCF (HART Communication
Foundation).
*3: PROFIBUS is the communication protocol for factory
and process automation that the PROFIBUS Organization
recommends. Instead of analog control with a
conventional analog signal (4-20mA), it is the fieldbus
which digitizes all signals. Flowmeters support
PROFIBUS-PA.
Fluid to be
measured
Signal cable
Excitation cable
LF470
Detector
Figure 1. Configuration Diagram
detector.Combined
with
2
communicator)
3
interface is available
Power supply
4-20mA dc output
and pulse output
LF612 or LF232
Converter
LF470
Figure 2. Electromagnetic Flowmeter
LF470/LF612
Certification number
Specifications
Overall Specifications
Measurement range in terms of flow velocity:
0–1.0ft/s to 0–32.8ft/s (0–0.3 m/s to 0–10 m/s )
Accuracy: The overall accuracy combined with the
LF612 or LF232 converter is shown in the
following table.
Flow rate as a
percent of range
(0.3-1.0m/s )
50 ∼ 100 %
± 0.8% of FS
0 ∼ 50 %
± 0.8% of FS
Note: The accuracy is measured under standard
operating conditions at Toshiba's calibration facility.
Fluid conductivity: 50µS/cm minimum
Fluid temperature:
Pipe connection material
Stainless steel and other metals
Polyvinyl chloride
(shock-resistant)
Ambient temperature: 14 to 140 °F (–10 to +60 °C )
Structure: IP67
Power consumption:
・When combined with the LF612 converter:
approximately 12W (20VA)
・When combined with the LF232 converter:
approximately 14W (25VA)
LF470/LF612
1/10",1/6",1/4" (2.5,4,6mm )
LF612
Z01207
Accuracy
1.0-3.3ft/s
3.3-32.8ft/s
(1.0-10m/s )
± 0.8% of rate
± 0.4% of FS
Fluid temperature
14 to 248 °F
(−10℃∼+120℃)
14 to 140 °F
(−10℃∼+60℃)
TIC-LF470B