Principle, structure

When the airflow enters the flowmeter, it first passes through a specially designed rectifier and accelerates. Under the action of the fluid, the turbine overcomes the resistance torque and friction torque and begins to rotate. When the torque reaches equilibrium, the speed stabilizes, and the speed of the turbine is proportional to the gas flow rate. The magnetic field is periodically changed by the magnet on the rotating transmission disk, so that the pulse generator outputs a pulse signal with a frequency proportional to the flow rate. The microprocessor in the volume correction instrument counts and processes the pulse signal to obtain the standard volume flow rate of the gas, and accumulates it to obtain the total standard volume.

characteristic

Equipped with a built-in battery pack, internal data can be stored for a long time without external power supply.

Adopting low-power high-tech, both internal and external power sources can work, and the internal battery can be used continuously for more than five years.

A GPRS wireless data transmission system can be formed by matching with a data collector through an RS485 interface, which facilitates automated management. The RS485 communication protocol complies with the MODBUS specification.

The header can rotate 180 ° freely, making installation convenient.

● Independent movement design, good interchangeability and easy maintenance.

Technical Parameter

Conditions of Use
Environmental temperature:	-30℃～+60℃；
Atmospheric pressure:	70kPa～106kPa；
Medium temperature:	-20℃～+80℃；
Relative humidity:	5% to 95%.
Accuracy level:
Level 1.0	Qmin～0.2Qmax ±1.0% 0.2Qmax～min ±2.%
	0.2Qmax～min ±2.%
Level 1.5	Qmin～0.2Qmax ±1.5% 0.2Qmax～min ±2.5%
	0.2Qmax～min ±2.5%
Real time data storage function
Start stop record:	The latest 2000 start stop times, total volume, and net flow records. Factory default settings.
Diary entry:	Record the temperature, pressure, standard volume flow rate, and total amount at midnight for the last 2000 days.
Electrical performance indicators
External power supply:	+24VDC±15%
Internal power supply:	1 set of 3.6V lithium batteries
Whole machine power consumption:	External power supply,<1W.
	Internal power supply, average power consumption ≤ 1mW, continuous for five years
Pulse output mode:	Pulse signal under working conditions
	High level ≥ 20V, low level ≤ 1V.
Communication mode:	RS485 communication (using optoelectronic isolation RS485 communication module) remotely displays the temperature, pressure, and standard volume flow rate and total standard volume of the medium after temperature and pressure correction
Explosion proof function:	ExdⅡBT4
Protection level:	IP65

Range parameters under standard conditions

Typical error curve of flowmeter

Typical pressure loss curve of flowmeter

The pressure loss of the flowmeter is calculated according to the following formula (1) to determine the pressure loss △ P of the flowmeter during operation. The maximum pressure loss of the flowmeter must be

Condition (2) must be met to ensure the normal use of the flowmeter. When the pressure loss does not meet the following formula, a larger specification should be selected.

The pressure loss can be calculated using the following formula:

In the formula:

ρ n: The density of the measured gas at standard conditions (20 ℃, 101.325kPa); Δ P1: Under the same operating flow rate, the pressure loss of the flowmeter when the medium is dry air with a density of 1.205 kg/m3 (as shown in Figure 3);

Pa: Local atmospheric pressure (kPa);

Pg: medium gauge pressure (kPa);

Pn: Standard atmospheric pressure (101.325kPa)

Tn: Absolute temperature under standard conditions (293.15K)

Tg: Absolute temperature under medium operating conditions (273.15+t) K Zn

Zg: refers to the gas compression coefficient under standard and working conditions, respectively. The pressure loss should meet the following conditions: P1- △ Pmax ≥ PLmin...... (2) In equation: P1: the minimum working pressure of the medium at maximum flow rate; △ Pmax: The maximum pressure loss of the flowmeter at its maximum flow rate during operation; PLmin: The minimum inlet pressure required for the use of gas tools.

FR90 Flow Range and Pressure Comparison Table

External dimensions

Model Selection Table

FR90-

Gas turbine flowmeter

orifice

DN25 DN32 DN40 DN50 DN65 DN80 DN100 DN125 DN150 DN200 DN250 DN300

Application range range (precise calibration)

Range range under A pressure value

Range range under pressure value B

Range range under C pressure value

Connection method

Flange connection

accuracy

Accuracy 1.0%

Accuracy 1.5%

Accuracy 2.0%

Voltage resistance level

EN 1092-1(DIN) PN10

A150

ASME B16.5(ANSI)CLASS150

EN 1092-1(DIN) PN16

A300

ASME B16.5(ANSI)CLASS300

EN 1092-1(DIN) PN25

A600

ASME B16.5(ANSI)CLASS600

EN 1092-1(DIN) PN40

A900

ASME B16.5(ANSI)CLASS900

EN 1092-1(DIN) PN63

A1500

ASME B16.5(ANSI)CLASS1500

EN 1092-1(DIN) PN100

A2500

ASME B16.5(ANSI)CLASS2500

EN 1092-1(DIN) PN250

J10

JIS 10K

EN 1092-1(DIN) PN400

J20

JIS 20K

Special standards for product application areas

System power supply mode

12 to 24V DC

86 to 265V DC

3.6V lithium battery (for pulse signal or display selection only)

Material of the liquid receiving body

Stainless steel 1.4301 (304)

Stainless steel 1.4435 (316L)

Internal impeller and accessory material

430F stainless steel

Stainless steel 1.4435 (316L)

Hastelloy C

Bearing material

Stainless steel 440C ball bearing (non water environment)

Ceramic journal bearings

signal type

Pulse+4 to 20mA current signal

Pulse+RS485 communication

(Special alternative) VARIO

Customized with special parameters

The above selection table does not include selection codes. If you need selection codes, please contact us or fill in your information