Active Member
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[China]
Address: No.21, Lane 697, Guangfulin Road, Songjiang District, Shanghai, China
Contact name:Nancy Zhao
Melan Measurement & Control Instruments (Shanghai) Co.,Ltd. |
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Portable Velocity Current Meter with 24 Hours Continuous Working
HT Handheld Reader
I. HT-A Type Handheld Reader
1. Introduction
Portable current velocity meter is an equipment used in water conservancy for velocity flow measurement, designed for hydro-logical stations,mining factories, environment monitoring stations, farm irrigation, hydro-geology and so on. Portable current velocity meter is composed of propeller velocity meter, HT type handheld reader and measuring bars. Full set of instruments is in the aluminum-alloy box.When using, you can assemble it as a body and connect the signal cable, then the velocity of every open channel can be measured. And it can automatically display the velocity and present the flow of sectional areas.
The instrument is ligHL and convenient with simple structure. It has low power consumption, complete function, high automation degree, stability and reliability, which complies with the national measurement standards.
2. Principle
This instrument is designed based on the theory of areas of open channel’s velocity. After measuring the velocity, the flow can be: Q=V·S(S is sectional area)
(1) Velocity Measurement
When measuring velocity, propeller velocity meter will be pushed by water power. The built-in signal apparatus produces RPM signal. The formula below can calculate velocity:
V: the average velocity(m/s)
B/K: the water power pitch of blades
C/a: velocity constant
T: lasting time(s)
N: the number of signal is T time
K/b and C/a are constants
Q: Flow
Remarks: When measuring, you can set T and then measure N, so the velocity and flow can be automatically calculated.
(2)Flow Calculation
The measurement of velocity is based on the theory of areas of open channel’s velocity. First, you can measure velocity and then multiply sectional area, so the flow can be gotten.
3. Specification
II. HT-B Type Handheld Reader
1. Introduction
Portable current velocity meter is an equipment used in water conservancy for velocity flow measurement, designed for hydro-logical stations,mining factories, environment monitoring stations, farm irrigation, hydro-geology and so on. Portable current velocity meter is composed of propeller velocity meter, HT type handheld reader and measuring bars. Full set of instruments is in the aluminum-alloy box.When using, you can assemble it as a body and connect the signal cable, then the velocity of every open channel can be measured. And it can automatically display the velocity and present the flow of sectional areas.
The instrument is light and convenient with simple structure. It has low power consumption, complete function, high automation degree, stability and reliability, which complies with the national measurement standards.
2. Principle
This instrument is designed based on the theory of areas of open channel’s velocity. After measuring the velocity, the flow can be: Q=V·S(S is sectional area)
(1)Velocity Measurement
When measuring velocity, propeller velocity meter will be pushed by water power. The built-in signal apparatus produces RPM signal. The formula below can calculate velocity:
V: the average velocity(m/s)
B/K: the water power pitch of blades
C/a: velocity constant
T: lasting time(s)
N: the number of signal is T time
K/b and C/a are constants
Q: Flow
Remarks: When measuring, you can set T and then measure N, so the velocity and flow can be automatically calculated.
(2)Flow Calculation
The measurement of velocity is based on the theory of areas of open channel’s velocity. First, you can measure velocity and then multiply sectional area, so the flow can be gotten.
HL-B can automatically calculate the flow. At the same time, it can store 99 measured data.
3. Specification
I. LS20B Type Propeller Velocity Meter
1. Introduction
LS20B Type Propeller Velocity Meter had passed the technical appraisal appraise of the Ministry of Water Resources of the People’s Republic of China in 1986 and its performance had reached international advanced level of similar products. This product was awarded the Third Prize of Science and Technology Progress by the Ministry of Water Resources of the People’s Republic of China in 1988 and was honored as China state level new product in 1990. In 1993, it participated in the international flow meter test which was organized by United States Geological Survey(USGS) and its superb performance was well praised by American experts when compared with world famous brands such as American Price AA, Germany Occt-3, Britain Valeport BFM002 and so on.
2. Application
LS20B Type Propeller Velocity Meter is a kind of large-range hydro-logical flow meter, which is applicable to measure high, medium, and low flow rate of rivers, lakes, channels, reservoirs and so on. It can also be used for measuring high velocity or ultrahigh velocity flow rate in pressure pipe of power station and some scientific experiment.
3. Features
4. Specification
Velocity range:0.05~15m/s
Turning propeller diameter: Ø120mm
Propeller hydraulic pitch: H=200mm
Depth range: 50m
Measuring bar: Ø20mm*3.0m(can be discharged into three sections)
Signal frequency: two signals/rotation
Working temperature: 0-40℃
Verification formula relative deviation: ƍ<±1.5%(V≥Vk); ƍ<±5.0%(V<Vk)
Suspended Sediment Concentration: ≤50kgs/m³
Continuous working time: 24 hours
Switch contact capacity: current≤50mA, voltage≤6V
Material: Direction Indicator & Tail: ABS
Others: stainless steel SS304
N.W.:Appox.1.0kgs
