Fork level switch

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A tuning fork switch is a new type of liquid level switch. Inspired by crystal a tuning fork produce…

A tuning fork switch is a new type of liquid level switch. Inspired by crystal a tuning fork produces an vibration, when the tuning fork is liquid submerged change vibration frequency, the frequency change detected by electronic circuit and a switch output.

Tuning fork type liquid level switch is also known as "electric float" use ball float liquid level switch and the scaling, agitation, turbulence, air bubble, vibration and other reasons lead to cannot use the ball float liquid level switch is applicable to occasions "tuning fork type liquid level switch". Due to the non-moving parts of the liquid level switch, it is a replacement product for the float liquid level switch. The product is widely used in petrochemical, light industry, food, water treatment, etc., and to the level of the liquid level.

Noil technical parameters:

Supply: 24VDC (standard); 220 vac (optional)

Output: SPDT relay (single pole double throw)

Ambient temperature: - 20 ℃ ~ 70 ℃

Process temperature: - 40 ℃ ~ 150 ℃

Process pressure: less than 2MPa

Media density: minimum 0.6 g/cm3

Delay: 1 ~ 50s (optional)

Process connection: 1 "NPT thread installation (standard); flange installation (optional); BSPT (optional)

Blowout: Exd II CT4 (optional)

Noil switch type:

Common type fork type liquid level switch

The type of a long tuning fork switch

Embalmed fork type liquid level switch

How it works:

Working principle of the tuning fork level switch type according to the materials on the vibration of a tuning fork with or without resistance, ascertain whether material level reach or exceed a certain height, and signal on and off, this principle does not require significantly mechanical movement, driving power is small, don't have to be calibrated, fast and low cost. Simple mechanical structure, no mechanical parts, no maintenance, no abrasion, long service life, sensitive and reliable.

Sensor made of elastic good metals, a tuning fork generally use stainless steel materials, such as SS316. The metal itself to determine the natural frequency, such as with the frequency of the alternating force and its inherent frequency is consistent, the fork is in a state of resonance, due to the ambient air on microwave vibration resistance, the energy loss in the metal inside and very few, so just tiny driving power can maintain a strong vibration.

Sensor to the inherent frequency of vibration, a tuning fork when hitting a tuning fork liquid or other material, its inherent vibration frequency is reduced, energy consumption on the interparticle friction material, forcing sharp attenuation and vibration amplitude, frequency number activated liquid level switch, on-off signal is produced.

Tuning fork level switch sensor is a driving force in order to provide a tuning fork alternating, using the amplifying circuit of piezoelectric element applied alternating electric field, by the inverse piezoelectric effect, mechanical force effect on the fork body. Using a set of piezoelectric elements to detect vibrations, it transforms the vibrational energy into a weak alternating electrical signal. The electronic amplifiers and the phase-shift circuits, which magnify the signal of the oscillator, move the phase of the oscillator, and apply it to the driving component to form a closed-loop oscillator.

In the closed loop, the machinery and electricity, fork is one of the joint body, if the material resistance to vibration, positive feedback of the amplitude and phase will be significantly changed, destroyed the oscillation condition, it will clear up. As long as the output of the amplifying circuit is connected to the appropriate device, it is not difficult to get the switch signal.

Product features:

Adaptability: different electrical parameters and densities of liquid are not affected by measurement. The conditions of scale, agitation, turbulence, bubble, vibration, medium viscosity, high temperature, high pressure, etc.

No need to adjust: because the detection of the limit switch of the tuning fork is not affected by the electric parameters and the density of the dielectric, no matter the measurement of the liquid, it is not necessary to adjust.

Avoid maintenance: because the detection of the limit switch of the tuning fork is done by electronic circuit, no moving parts, so once installed, it is not necessary to maintain.

Typical application:

Tap water, mineral water, paper pulp, waste water and mud, glue, dye, acid and alkali solution, can produce gas liquid, beer, beer yeast, beverage, diesel and other dangerous places, liquid solid powder

Performance indicators:

Supply: 24VDC (standard)

220 vac (optional)

Output: SPDT relay (single pole double throw)

Output capacity: 220VAC 5A

24 VDC 3 a

Ambient temperature: - 20 ℃ ~ 70 ℃

Medium temperature: - 40 ℃ ~ 150 ℃

Job stress: less than 2MPa

Media density: minimum 0.6 g/cm3

Forked material: 316 stainless steel

Action point: vertically inserts 25mm in water

Corresponding time: < 0.5 s

Delay: 1 ~ 50s (optional)

Power consumption: 0.5 W

High and low alarm: the site can be set to HLFS (high alarm mode) or LLFS (low alert mode)

Electrical interface: g1/2"

Process connection: 1 "NPT thread installation (standard, optional BSPT); flange installation (optional)

Enclosure protection: IP65

Blowout: Exd II CT4