Единицы | бар | мм рт.ст. | мм вод.ст. | атм (физич.) | кгс/м2 | кгс/см2 (технич. атм.) | Па | кПа | Мпа |
---|---|---|---|---|---|---|---|---|---|
1 бар | 1 | 750.064 | 10197,16 | 0.986923 | 10.1972 ∙ 103 | 1,01972 | 105 | 100 | 0.1 |
1 мм рт.ст. | 1.33322 ∙10-3 | 1 | 13,5951 | 1.31579 ∙10-3 | 13,5951 | 13.5951 ∙10-3 | 133.322 | 133.322 ∙10-3 | 133.322 ∙10-6 |
1 мм вод.ст. | 98.0665 ∙10-6 | 73.5561 ∙ 10 -3 | 1 | 96.7841 ∙10-6 | 1 | 0.1∙10-3 | 9.80665 | 9.80665 ∙10-3 | 9.80665 ∙10-6 |
1 атм | 1.01325 | 760 | 10.3323 ∙103 | 1 | 10.3323∙ 103 | 1.03323 | 101.325 ∙ 103 | 101.325 | 101.325 ∙10-3 |
1 кгс/м2 | 98,0665 ∙10-6 | 73.5561 ∙ 10 -3 | 1 | 96.7841 ∙10-6 | 1 | 0.1∙10-3 | 9.80665 | 9.80665 ∙10 -3 | 9.80665 ∙10-6 |
1 кгс/см2 | 0,980665 | 735.561 | 10000 | 0.967841 | 10000 | 1 | 98.0665 ∙ 103 | 98.0665 | 98.0665 ∙10-3 |
1 Па | 10 -5 | 7.50064 ∙10-3 | 0,1019716 | 9.86923 ∙10-6 | 101.972 ∙ 10-3 | 10.1972 ∙10-6 | 1 | 10 -3 | 10 -6 |
1 кПа | 0.01 | 7.50064 | 101,9716 | 9.86923 ∙10-3 | 101.972 | 10.1972 ∙10-3 | 103 | 1 | 10 -3 |
1 МПа | 10 | 7.50064 ∙103 | 101971,6 | 9.86923 | 101.972 ∙103 | 10.1972 | 106 | 103 | 1 |
К системе СИ относятся: Инженерные единицы:
Бар
1 бар = 0,1 Мпа 1 мм рт.ст. = 13.6 мм вод.ст.
1 бар = 10197.16 кгс/м2 1 мм вод.ст. = 0.0001кгс/см2
1 бар = 10 Н/см2 1 мм вод.ст. = 1 кгс/м2
1 атм = 101.325 ∙ 103 Па
Па
1 Па = 1000МПа
1 МПа = 7500 мм. рт. ст.
1 МПа = 106 Н/м2
Pressure sensing quartz crystal sensor RKMA-P. The RKMA-P is designed to work in composition of precision electronic transducers, pressure gauges and pressure controllers with a frequency or digital output signal as a converter of current values of pressure to frequency.
The RKMA-P is designed to work in composition of precision electronic transducers, pressure gauges and pressure controllers with a frequency or digital output signal as a converter of current values of pressure to frequency.
RKMA-R - manometric sensor, consists of a membrane 3, on which a force-sensitive piezoresonance element in the form of a dual tuning fork of flexural vibrations is rigidly fixed. The piezoelectric element is located in an evacuated cavity formed by the gasket 2 and the cover of the sensor 1. All the details of the resonator are made of single-crystal quartz. Under the action of sensor, the membrane bends, stretching or compressing the force-sensitive piezoelectric element, and the RKMA-P resonance frequency changes due to the pressure-acting conversion function.
A number of RKMA-R, differing in design features and ranges of working pressure is produced.
Parameters | Specifications and remarks | Units | ||||
Electrical characteristics |
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Model of the sensor |
RKMA-P-1 |
RKMA-P-3 |
RKMA-P-4 |
RKMA-P-21 |
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Frequency Range, fO |
40.000…48.000 |
kHz |
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Series resistance typ./max., RS |
120/ 200 |
150/ 250 |
kOhm |
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Drive level max., DL |
4.0 |
µW |
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Insulation resistance min., IR |
400 |
MOhm |
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Motional characteristics |
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Strait: F(P)=fO +A1*P +A2*P2+ A3*P3, where: F(P) – sensors’s frequency at current value of pressure P (Hz), Inverse: P(F)=BO +B1 x (F-F0) +B2 x (F-F0)2+ B3 x (F-F0)3 where: P(F) – pressure value corresponding to the current frequency of the sensor F(MPa), F0, B0, B1, B2, B3 – coefficients.* |
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Overalls |
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Operating Temperature, TOPR (typ/max) |
-60…+80 / -196…+180** |
°C |
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Temperature accuracy in the working temperature interval at P=0.1 MPa, no more |
± 20 |
Hz |
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Resolution |
0.005 (0.1) |
Hz(ppm) |
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Aging first year/10 years max |
± 15 / ± 40 |
ppm |
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Vibration Resistance (vibration from 10 to 2000 Hz with acceleration 5g during 8 houers), DF/F0 |
±5 max. |
ppm |
* the coefficients of the function are determined by individual graduation, with connecting RKMA-P-1 (21, 3, 4) to the oscillator.
** when ordering, you must specify the desired operating temperature range.
Temperature sensing quartz crystal RKT206 may be used for compensation of a temperature deviation of RKMA-P.
Precision electronic transducers, pressure gauges and pressure controllers (with the ability to compensate for temperature error) with an accuracy class up to 0.01 are developed and manufactured based on RKMA-R.
Inverse temperature-compensated conversion function: Р(Fp, T) = C0 + C1 × (T - T0) + C2 × (T - T0)2 + C3 × (Fp - Fp0) + C4 × (Fp - Fp0)2 + C5 × (Fp - Fp0) × (T - T0)
where Fp is the current value of the frequency of the crystal PKMA-P-OS-21 (Hz);
T is the current temperature value (°C);
T0, Fp0, C0, C1, C2, C3, C4, C5 are the coefficients of the transformation function determined as a result of calibration.
There are 4 main versions of the quartz manometric absolute pressure sensors RKMA-R:
UNITS: millimeters
RKMA-P-1 |
RKMA-P-3 |
RKMA-P-4 |
RKMA-P-21 |
1- Cover; 2- Gasket; 3- Membrane; 4- Contact pads. |
Working pressure intervals |
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|
The upper limit of the interval of working absolute pressure P |
Unit |
Sensitivity (linear coefficient) A1 ± 5...20% FS) |
Units |
Overall dimensions, no more |
Units |
RКМА-0.1-1 (3;4) |
0.1 |
MPa |
22000 |
Hz/MPa |
26 х 24 х 4.0 (6.0) |
mm |
RКМА-0.25-1 (3;4) |
0.25 |
10000 |
26 х 24 х 4.2 (6.2) |
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RКМА-0.4-1 (3;4) |
0.4 |
7800 |
26 х 24 х 4.3 (6.3) |
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RКМА-0.6-1 (3;4) |
0.6 |
2800 |
26 х 24 х 4.6 (6.6) |
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RКМА-1.0-1 (3;4) |
1.0 |
2100 |
26 х 24 x4.1 (6.1) |
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RКМА-1.6-1 (3) |
1.6 |
1100 |
26 х 24 х 4.4 (6.4) |
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RКМА-2.5-1 (3) |
2.5 |
1000 |
26 х 24 x4.6 (6.6) |
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RКМА-4.0-1 (3) |
4.0 |
500 |
26 х 24 x4.8 (6.75) |
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RКМА-6.0-1 (3) |
6.0 |
300 |
26 х 24 х 6.1 (8.1) |
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RКМА-10.0-1 (3) |
10.0 |
160 |
26 х 24 х 5.3 (7.3) |
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RКМА-16.0-1 (3) |
16.0 |
130 |
26 х 24 х 5.7 (7.7) |
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RКМА-0.1-21 |
0.1 |
20800 |
ø15 х 1.25 |
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RКМА-0.16-21 |
0.2 |
20800 |
ø15 х 1.8 |
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RКМА-0.25-21 |
0.25 |
15000 |
ø15 х 1.85 |
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RКМА-0.4-21 |
0.4 |
6000 |
ø15 х 1.95 |
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RКМА-0.6-21 |
0.6 |
3800 |
ø15 х 2.25 |
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RКМА-1.0-21 |
1.6 |
200 |
ø15 х 2.35 |