electromagnetic flowmeter_Anhui Honglin Instrument Cable Co., Ltd.

electromagnetic flowmeter

The measurement principle of electromagnetic flowmeter is Faraday's law of electromagnetic indu…

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Description

summary:
The measurement principle of electromagnetic flowmeter is Faraday's law of electromagnetic induction. The main components of the sensor are: measuring tube, electrode, excitation coil, iron core and yoke shell. Electromagnetic flowmeter is mainly used to measure the volume flow of conductive liquid and slurry in closed pipeline. Including acid, alkali, salt and other strong corrosive liquid. Electromagnetic flowmeter is widely used in petrochemical, iron and steel metallurgy, water supply and drainage, water irrigation, water treatment, environmental protection sewage total control, papermaking, medicine, food and other industrial and agricultural sectors flow measurement and control; It is suitable for measuring the total amount of conductive liquid.
Product features:
1. Programmable frequency low frequency rectangular wave excitation improves the stability of flow measurement and low power loss;
2. It adopts 16 bit embedded microprocessor with high speed and high precision;
3. All digital data processing, strong anti-interference ability, reliable measurement, high precision, flow measurement range can reach 150:1;
4. Ultra low EMI switching power supply, suitable for wide range of power supply voltage variation, good anti EMC performance;
5. Chinese menu operation, easy to use, easy to operate, easy to learn and understand;
6. High definition backlight LCD display;
7. It has two-way flow measurement, two-way total cumulative function, current and frequency with two-way output function;
8. There are three integrators in the interior, which can display the positive cumulative quantity, the reverse accumulated quantity and the difference accumulated quantity;
9. With RS485 or RS232 digital communication signal output
10. With conductivity measurement function, it can judge whether the sensor is empty;
11. The constant current excitation current range is large, which can be used with different companies and different types of electromagnetic flow sensors;
12. It has the function of self inspection and self diagnosis;
13. SMD devices and surface mount (SMT) technology are used to improve the circuit reliability;
14. The internal design of the instrument has a non power down clock, which can record 16 power down times.
Main technical data:
Technical data of whole machine and sensor

Executive Standards
Nominal diameter	10、15、20、25、32、40、50、65、80、100、125、150、200、250、300、350、400、500、600、700、800、900、1000、1200、1400、1600、1800、2000、2200、2400、2600、2800、3000
***High velocity	15m／s
Accuracy	DN10~DN600	5% (flow rate ≥ 1m / s); ± 3mm / S (flow rate < 1m / s)
	DN700~DN3000	5% (flow rate ≥ 0.8m / s); ± 4mm / S (velocity < 0.8m / s)
Fluid conductivity	≥5uS／cm
Nominal pressure	4.0MPa		1.6MPa		1.0MPa			0.6MPa	6.3、10MPa
	DN10~DN80		DN100~DN150		DN200~DN1000			DN1200~DN2000	Special order
ambient temperature	sensor		-25℃～+60℃
	Converter and all in one		-10℃～+60℃
Lining material	Polytetrafluoroethylene, polychloroprene rubber, polyurethane, perfluoroethylene propylene (F46), screening PFA
***High fluid temperature	All in one		70℃
	Separable type		Polychloroprene rubber lining			80℃； 120 ℃ (indicate when ordering)
			Polyurethane lining			80℃
			PTFE lining			100℃； 150 ℃ (indicate when ordering)
			Perfluoroethylene propylene (F46)
			Screening PFA
Signal electrode and grounding electrode materials	Stainless steel 0crl8nil2m02ti, Hastelloy C, Hastelloy B, titanium, tantalum, platinum / iridium alloy, stainless steel coated tungsten carbide
Electrode scraper mechanism	DN300～DN3000
Connection flange material	carbon steel
Grounding flange material	Stainless steel 1Crl8Ni9Ti
Imported protective flange material	DN65~DN150			Stainless steel 1Crl8Ni9Ti
	DN200~DN1600			Carbon steel + stainless steel 1Crl8Ni9Ti
Enclosure protection	DN 10 ～ dn3000 separate type rubber or polyurethane lining sensor						IP65 or IP68
	Other sensors, integrated flow meters and separate converters						IP65
Spacing (split type)	The distance between transducer and sensor is generally less than 100m

Converter technical data

Power Supply	communication	85～265V，45～400Hz
	direct	11～40V
	lithium battery
Operation key and display	Button type	All parameters can be set and selected by 4 film keys, and the converter can be programmed by PC (RS232); 3-line LCD with wide viewing angle, wide temperature and backlight display; The first line shows the flow value; The second line shows the flow unit; The third line shows the percentage of flow, total forward, total reverse, total difference, alarm, flow rate.
Operation key and display	Magnetic key type	Two magnetic keys are used to select and reset the display parameters, and PC (RS232) is used to set and program the converter; 2-line LCD with wide viewing angle, wide temperature and backlight display: Line 1: magnetic key selection: display flow percentage, total forward, total reverse, total difference, alarm and flow rate. Line 2: shows the flow.
Internal integrator	Positive total, reverse total and difference total.
output signal	Unidirectional analog output	Full isolation, load ≤ 600D. (20mA); Upper limit: 0 ~ 21ma, 1mA for each gear; Lower limit: 0 ~ 21ma, 1mA for each gear; Positive and negative flow output mode programming.
	Bi directional analog output	The lower limit is 0 or 4mA, and the others are the same as unidirectional analog output.
	Bidirectional pulse output	The two outputs correspond to forward and reverse flow respectively, with frequency of 0-800hz, upper limit of 1-800hz, and 1Hz of each gear; Square wave or selected pulse width, the upper limit of selected pulse width is 2.5s, 1ms for each gear; Passive isolation transistor switch output, can absorb 250mA current, withstand voltage 35V.
	Two way alarm output	It can alarm (program) high / low flow, air pipe, fault state, positive and negative flow, analog over range, pulse over range, pulse small signal removal, and output polarity is optional; With isolation protection transistor switch output, can absorb 250mA current, withstand voltage 35V (not isolated from pulse output)
Digital communication		RS232，RS485，HART

Selection of lining

Lining material	main performance	***High medium temperature		Scope of application
Lining material	main performance	All in one	Separable type
Polytetrafluoroethylene (F4)	It is a kind of plastic with stable chemical properties. It is resistant to boiling hydrochloric acid, sulfuric acid, sodium hydroxide and aqua regia. It is also resistant to concentrated alkali and various organic solvents. It is not resistant to the corrosion of chlorine trifluoride, high temperature chlorine trifluoride, high flow rate liquid fluorine, liquid oxygen and self oxygen.	70℃	100 ℃ 150 ℃ (special order required)	1. Strong corrosive media such as concentrated acid and alkali. 2. Sanitary media.
Perfluoroethylene propylene (F46)	The wear resistance and negative pressure resistance of F4 are higher than that of F4.		ditto
Polyfluoroethylene (FS)	The upper limit of applicable temperature is lower than that of polytetrafluoroethylene, but the cost is also lower.		80℃
Polychloroprene rubber	1. It has excellent elasticity, high breaking force and good wear resistance. 2. It is resistant to corrosion of low concentration acid, alkali and salt medium, but not to oxidation medium.		80 ℃ 120 ℃ (special order required)	Water, sewage and slurry with weak abrasion resistance.
Polyurethane rubber	1. The wear resistance is very strong. 2. Poor corrosion resistance.		80℃	Mineral slurry, coal slurry and mud with neutral strong abrasion

Selection of inlet protection flange and grounding flange (or grounding ring)

Flange type	Scope of application
Grounding flange (or grounding ring)	Suitable for non-conductor pipes, such as plastic pipes, but not required for sensors with grounding electrodes.
Inlet protection flange	When the medium has strong wear resistance.

Selection of electrode

Electrode material	Corrosion resistance and wear resistance
Stainless steel 0crl8nil2m02ti	It is suitable for industrial water, domestic water, sewage and other weakly corrosive media. It is suitable for petroleum, chemical, steel and other industrial sectors and municipal, environmental protection and other fields.
Hastelloy B	It has good corrosion resistance to all concentrations of hydrochloric acid below boiling point, as well as non chlorinated acid, alkali and non oxidizing salt solution such as sulfuric acid, phosphoric acid, hydrofluoric acid and organic acid.
Hastelloy C	It can resist the corrosion of non oxidizing acid, such as × ×, mixed acid, or mixed medium of chromic acid and sulfuric acid, as well as the corrosion of oxidizing salts such as FC ＋, Cu ＋ or containing other oxidants, such as hypochlorite solution higher than normal temperature and seawater corrosion
titanium	It can resist the corrosion of seawater, various chlorides and hypochlorites, oxidizing acids (including fuming sulfuric acid), organic acids and alkalis. It is not resistant to the corrosion of pure reducing acid (such as sulfuric acid and hydrochloric acid), but the corrosion is greatly reduced if the acid contains oxidants (such as × ×, FC ＋, Cu ＋).
tantalum	It has excellent corrosion resistance and is similar to glass. In addition to hydrofluoric acid, fuming sulfuric acid and alkali, it can almost resist the corrosion of a chemical medium (including hydrochloric acid with boiling point, * * *) and sulfuric acid below 150 ℃). In the alkali Diao; Corrosion resistance.
Platinum / titanium alloy	It is resistant to almost all chemical media, but not suitable for aqua regia and ammonium salts.
Stainless steel coated with tungsten carbide	It is used for non corrosive and strong wear medium.
Note: since there are many kinds of media and their corrosivity is affected by complex factors such as temperature, concentration and flow rate, this table is for reference. Users should make their own choice according to the actual situation. If necessary, the corrosion resistance test of the materials to be selected, such as coupon test, should be carried out.

Selection of electromagnetic flowmeter

Range confirmation
In general, the flow rate of the measured medium of the general industrial electromagnetic flowmeter should be 2-4m / s. under special circumstances, the flow rate of the medium at low speed should not be less than 0.2m/s, and the flow rate should be higher than or equal to 0.2m/s
It should be no more than 8m / s. If the medium contains solid particles, the flow rate should be less than 3m / s to prevent excessive friction between lining and electrode; For viscous fluids,
The flow rate can be greater than 2m / s. The larger flow rate is helpful to automatically eliminate the effect of sticky substances attached to the electrode, which is conducive to improving the measurement accuracy.
Under the condition that the range Q has been determined, the diameter D of the flowmeter can be determined according to the range of the above flow rate v. the value is calculated by the following formula:
Q=π*3600D ² V/4
Q: flow (M ³/ h) D: inner diameter of pipeline V: velocity (M / s)
The range Q of the electromagnetic flowmeter should be greater than the expected large flow value, while the normal flow value should be slightly greater than 50% of the full scale of the flowmeter.

Reference flow range of electromagnetic flowmeter

Diameter mm	Flow range M ³/ h	Diameter mm	Flow range M ³/ h
φ ten	0.16~2.5	φ four hundred	250~4000
φ fifteen	0.4~6	φ five hundred	400~6000
φ twenty	0.6～12	φ six hundred	600~10000
φ twenty-five	1.0～16	φ seven hundred	800~12000
φ thirty-two	1.6~25	φ eight hundred	1000~16000
φ forty	2.5～40	φ nine hundred	1200~20000
φ fifty	4.0～60	φ one thousand	1600~25000
φ sixty-five	6.0～120	φ one thousand and two hundred	2500~30000
φ eighty	10~160	φ one thousand and four hundred	3000~50000
φ one hundred	16~250	φ one thousand and six hundred	3000~60000
φ one hundred and twenty-five	25~400	φ one thousand and eight hundred	5000~60000
φ one hundred and fifty	40~600	φ two thousand	6000~100000
φ two hundred	60~1000	φ two thousand and two hundred	1367.78～136778.4
φ two hundred and fifty	100~1600	φ two thousand and four hundred	1627.78～162777.6
φ three hundred	160~2500	φ two thousand and six hundred	1910.38～191037.6
φ three hundred and fifty	200~3000

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