Pressure Sensors Special Feature

Pressure Sensors Special Feature

1. Outline

A pressure sensor is a device that converts the pressure of a fluid such as a gas or liquid into an electrical signal. Broadly speaking, the pressure sensor references are divided into the following three types.

a. Gauge [based on “atmospheric pressure”]

b. Absolute [based on “absolute vacuum”]

c. Differential [Measures the difference between two pressures.]

2. Operating principles

Pressure sensors generally use a diaphragm that formed strain gauges on, and measure its strain (or deflection) due to applied force over the diaphragm area.

Our company, NIDEC COMPONENTS offer two types of pressure sensors as sensing methods: a method using a diffusion type semiconductor (Silicone MEMS) and a method using a thin film gauge with SUS diaphragm. Each type has its own characteristics, and we have a wide variety of pressure sensor products by properly using these two type methods according to the application and market requirements.

Let's take a closer look at the operating principle for each type.

Ⅰ. Silicone MEMS (Si-MEMS)

 

 

Si-MEMS diaphragm
cross-section drawing

The Si-MEMS utilizes the piezoresistive effect in which the electric resistivity varies depending on the stress applied to the resistors. A sensor chip is made of single-crystal silicon. The chip structure allows the diaphragm to deform once the chip receives pressure.

The four strain resistors, connected as shown in the schematic below, constitute a Wheatstone bridge circuit. This bridge circuit is driven by constant current (nominal 1.5 mA DC). When pressure is applied, the resistance values of R2/R3 increase while those of R1/R4 decrease, bringing about inequality in the bridge circuit and causing a voltage difference at the output end. This voltage difference turns into an output voltage proportional to the pressure. Even when negative pressure is applied, the polarities are also inverted to the same orientation as when a positive pressure is applied.

To explain the pressure and output characteristic, the deformation of the diaphragm is illustrated in a magnified manner in the diaphragm cross-section drawing on aboveright, but the degree of deformation is as so small as several micrometers. Therefore, the mechanical deformation of the diaphragm is hardly recognized in appearance.

Ⅱ. Thin film sensor (SUS diaphragm)

Thin film sensor
cross-section drawing

Ⅱ. Thin film sensor (with SUS diaphragm)

A thin film sensor is structured by forming a thin film gauge on a metal SUS diaphragm via an insulating film. When pressure is applied, the metal diaphragm deforms and the thin film gauge formed on the diaphragm distorts, which then detects changes in the resistance value of the gauge.

In a thin film sensor, as with Si-MEMS, four thin film resistors are connected as shown in the schematic below to constitute a Wheatstone bridge circuit. The thin film resistors are driven by constant voltage. The metal diaphragm deforms once it receives pressure, the thin film resistors formed on the diaphragm distort, which then detect any changes in the resistance value of the gauge. Thus, a voltage signal in proportion to the pressure can be obtained.

1. Milestones

We've been supplying pressure sensors for about 40 years, beginning with the manufacturing and sales of pressure sensors for electronic sphygmomanometers in 1980. Thanks to you, our pressure sensors are widely used in various industries such as semiconductor manufacturing equipment, industrial equipment, medical equipment, analysis equipment, measuring equipment, and hydraulic equipment such as machining centers.

The business base will be the Sano Plant in Tochigi Prefecture, Japan. We handle everything from sensor chips to final pressure sensor products, and today it has grown into a leading business of our company.

2. Abundant standard product lineup

We offer a variety of pressure sensor products with different product types, such as module types, built-in amplifier types, pressure switches that open and close the contacts of pressure-sensitive elements by applying a specific pressure value, and pressure gauges with a display function. We have a large selection.
The types of pressure sensor elements are the semiconductor Si-MEMS and the thin film sensor with SUS. Among them, there are two types of Si-MEMS methods; one is a silicon single crystal type dedicated to non-corrosive gas as a medium, and the other is a dual diaphragm structure type that is placed a SUS diaphragm in the wetted part, that can also apply for liquids as a medium. We use each of these sensor elements appropriately according to the application and environment, and develop them into various final products.

Method	Si-MEMS (Si single crystals)	Si-MEMS (Dual diaphragm)	Thin film sensor with SUS
Structure
	Si single-crystal element is bonded to the glass base by means of anodic bonding via Na ions contained in the glass. The Si single-crystal element directly receives the medium.	An SUS diaphragm is bonded to the housing by means of laser welding, and conveys pressure to the silicone sensor chip via the silicone oil.	A thin film gauge is formed by means of vapor deposition on a SUS diaphragm via an insulating film.
Media	Dedicated for noncorrosive gas	Gas or liquid that does not corrode the SUS material in the wetted part	Gas or liquid that does not corrode the SUS material in the wetted part
Features	• Although the characteristics change depending on the temperature, these models exhibit high reproductivity under certain temperatures. • Capable of receiving high pressure and outputting high voltage at a high accuracy (approx. 100 mV at rated pressure of 100 kPa) • Free from mechanical movable part, a long service life can be achieved • With a high mass productivity, manufacturing at a lower cost is achieved.		• Suitable for vacuum, high and low temperature applications • Exhibits less temperature-dependent characteristic change • Single-model mass-production leads to manufacturing at a lower cost • Compatible with electrolytic polishing
Our pressure sensor series lineup
Pressure transducer (Module)	P-2000, P-3000S	P-8300, P-8305, P-8505	―
Pressure transducer with Amp.	PA-20, PA-100, PA-500	P-7100, PA-750/758, PA-800, PA-830/838, PA-838-D, PA-850/858, PA-860/868	High vacuum: PA-920S/928S High temperature: PA-930/930-A
Pressure switch	PS20, PS30, PS40, PS6, PS60	PS8, PS83, PS85, PS86	High vacuum: PS91, PAS91
Pressure gauge Handheld digital manometer	PG-30, PG-200,PG-100N	PG-35, PG-35H, PG-75, PG-208, PG-100B	High vacuum: PG-20, PG-35L

*In addition, we have a standard lineup of two series of pressure indicators, PZ-30 and PZ-200.

In recent years, we've been aggressively releasing new products such as types with a built-in small amplifier with ratiometric output and types for high vacuum and high temperature using the thin film sensor elements with SUS, and we are expanding our business domain.

1. In-house integrated production

We manufacture in-house from sensor elements by making full use of semiconductor technology, and further develop and manufacture pressure sensor final products through processes such as mounting, temperature compensation, electronic circuit addition and casing, etc.

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  Silicone wafer ⇒ Sensor chip
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  Pressure sensor module
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  Pressure sensor products
  with amp.

A major feature of our pressure sensor is that we handle everything from development design to sensor element manufacturing process and product assembly process / calibration under the integrated quality control of our pressure sensor business based on high-mix low-volume production. Our strength lies in this business structure, which is capable of responding to special specifications and various customer needs in detail.

2. Special products (Customizations)

― Policy for custom support ―

Our policy for customizations is as follows:

Our pressure sensors have a total of 92 models, and the P/N of models is 1,992. Of these, Customizations, so-called Special products, accounts for nearly 80% of the total on a monetary basis, and as the results show, we have provided many custom products and services that meet the individual needs of the market and customers. Introduce some examples of the special products bellow.

Customization examples

Electrolytic polishing + Degreasing + Clean packaging

Electrolitic polishing / Degreasing / clean packaging are often required as essential for in-line piping applications in semiconductor manufacturing equipment. First, in "Electrolitic polishing", the flatness is improved by chemical polishing so that impurities do not remain in the pressure receiving part. In addition, "Degreasing" prevents contamination by cleaning the organic matter in the pressure receiving part. Similarly, "Clean packaging" prevents contamination from the outside and guarantees the clean condition of the pressure sensor product until it is used by the customer.

PA-750/758 series: Compatible with cable connectors and Direct cable from body

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  Standard model
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  (1) Cable with connectors
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  (2) Direct cable from body

The PA-750/758 standard series uses a connector cable that the body and cable can be attached and detached, and the cable tip has a lead wire. We have both achievements in supporting (1) the installation of designated tip connectors and (2) direct cable removal from the main unit.

PS20 series: Special fitting

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  Standard model
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  Special fitting

The PS20 standard series is M5 male screw or block M5 female screw, but we have made a proposal to meet the market needs to extend the tip of the block, make an hole for M5 female screw, and fix it with a mounting screw.

Other examples

Specification / Performance change

Appearance / shape change

Others

With our experience and expertise, we will propose the best products and services that meet your needs. Please feel free to contact us from the button below.

1. About Products

1. About cable specifications
Q. We want to fit a connector to a cable. Where can we find your cable specs?	Answer We want to fit a connector to a cable. Where can we find your cable specs? -- Answer -- For cable specifications for various pressure sensors, refer to the cable core diameter table.（PDF） Cable Conductor Size Table Cautions for when crimping contact pins 1. Select the correct conductor size and contact pin size recommended by the manufacturer. 2. trip the conductor insulation to the length specified by the manufacturer. 3. Use the crimping tool recommended by the manufacturer.
2. Scope of non-corrosive gases in medium
Q. You require that a pressure medium for use with P-2000 or P-3000S should be a non-corrosive gas. Can steam-laden air be used? If not, what model do you recommend?	Answer You require that a pressure medium for use with P-2000 or P-3000S should be a non-corrosive gas. Can steam-laden air be used? If not, what model do you recommend? -- Answer -- The P-3000S is designed to have a sensor chip in direct contact with the medium. Exposure to moisture will affect the characteristics of the sensing chip. Meanwhile, the PA-800 dual-diaphragm transducer is built to receive pressure with its stainless steel diaphragms and transmit the pressure via the sealed-in silicone oil, so that it can measure the pressure of steam or that of a liquid. Models of pressure transducers usable with steam-laden air include P-8300 and P-8505 (with no amplifier) as well as PA-750/758 and PA-830/838 (with an amplifier). Our recommended models of pressure switches include PS83 and PS85. Our recommended models of pressure gauges include PG-35 and PG-75. For more detailed information, refer to the section on the pressure media in the Product Guide. P-3000S Internal structure PA-800 Internal structure  Click here to check pressure sensor products. Pressure Sensors Product Guide
3. How to clear noises (Wiring shield cable)
Q. The transducer we use has a built-in amplifier. Its output fluctuates, and the cause seems to be noise. The side for mounting to the equipment is insulated. The shielding wires on the receiver side are not connected to anywhere during use. What measures should be implemented?	Answer The transducer we use has a built-in amplifier. Its output fluctuates, and the cause seems to be noise. The side for mounting to the equipment is insulated. The shielding wires on the receiver side are not connected to anywhere during use. What measures should be implemented? -- Answer -- The FG is insulated on both the equipment side and the receiver side, which suggests that noise propagation through the cables caused the output to fluctuate. Ground the shielding wires on the receiver side to reduce the influence of the noise. (a) Sensor is earthed (b) Sensor is insulated
4. How to set switch of pressure switch
Q. We intend to use a KF25 flange fitting for a PS91 vacuum switch for atmospheric pressure monitoring to detect when a vacuum heating oven is under atmospheric pressure. We are not sure how to select N1 and N2 and would like your advice. We imagine that the vacuum switch turns on when the pressure returns from vacuum to atmospheric pressure. How should the switch output be selected and set so that the vacuum switch turns on at -80 kPa when the pressure goes from atmospheric pressure to a vacuum?	Answer We intend to use a KF25 flange fitting for a PS91 vacuum switch for atmospheric pressure monitoring to detect when a vacuum heating oven is under atmospheric pressure. We are not sure how to select N1 and N2 and would like your advice. We imagine that the vacuum switch turns on when the pressure returns from vacuum to atmospheric pressure. How should the switch output be selected and set so that the vacuum switch turns on at -80 kPa when the pressure goes from atmospheric pressure to a vacuum? -- Answer -- In the case of an N1/P1-type PS91 switch, both SW1 and SW2 turn ON when the pressure rises. In the case of the N2/P2 Type, SW1 turns ON when the pressure drops, whereas SW2 turns ON when the pressure rises. For a configuration in which the SW turns ON when the pressure returns from a vacuum to atmospheric pressure and when the pressure goes from atmospheric pressure to -80 kPa, select the N2/P2 Type. PS91 N2/P2 type switch output operation Next, let us see how to set the switch. Before starting, prepare a PS-91-102V-N2-K2, a digital manometer, a pressure-regulating valve, a vacuum pump, a constant-voltage power supply, and a trimmer adjustment precision screwdriver. Be sure to connect the lead cables of the PS91 correctly to the power supply: the red lead cable is for connection to the plus side of the power supply, and the black lead cable is to be used as the common return cable. Set the power supply to the same voltage as that of the equipment. Then, connect the digital manometer to the pressure-regulating valve between the PS-91 and the vacuum pump according to the piping drawing below. First, let us set the SW to turn ON when atmospheric pressure is reached. With the vacuum pump OFF, adjust the pressure on the PS91 to atmospheric pressure. The operation mode of the SW2 of the PS91 is such that it turns ON when the pressure rises. In other words, the point at which the operation indicator LED comes on when the pressure setting trimmer 2 on the backside is turned clockwise is the point at which SW2 turns ON when atmospheric pressure is reached. Then, with the pressure-regulating valve opened, turn the vacuum pump ON and look at the digital manometer to make sure that the vacuum is reached. After that, turn OFF the vacuum pump and vent it to the atmosphere. Make sure that the operation indicator LED of the PS91 comes on when the digital manometer reads 0. Next, let us set the SW to turn ON when the pressure drops from atmospheric pressure to -80 kPa. First, with the pressure-regulating valve closed, turn the vacuum pump ON. Open the valve gradually to adjust the pressure to -80 kPa. The operation mode of the SW1 of the PS91 is such that it turns ON when the pressure drops. In other words, the point at which the operation indicator LED comes on when the SW1 on the back is turned clockwise is the point at which the switch turns ON when the pressure reaches -80 kPa. After that, turn OFF the vacuum pump and allow the pressure to return to atmospheric pressure. After seeing that the pressure has returned to atmospheric pressure, close the valve and turn ON the vacuum pump. Open the pressure-regulating valve gradually and make sure that the operation indicator LED comes on when the digital manometer reads -80 kPa. The knack for pressure setting is adjusting the pressure setting trimmer and the pressure-regulating valve slowly.
5. Mounting on PCB (Manual soldering required)
Q. We want to solder a P-2000 onto a printed circuit board. What are your recommended soldering conditions?	Answer We want to solder a P-2000 onto a printed circuit board. What are your recommended soldering conditions? -- Answer -- For our recommended soldering conditions for different types of sensors available from us, refer to the Recommended Soldering Conditions Table.（PDF） Recommended soldering conditions Cautions for soldering 1. Install a PCB-mountable P-2000, P-3000S, or PA-100 onto a PCB by hand-soldering instead of flow-soldering or reflow-soldering. 2. Remove flux residues not by immersion in the cleaning liquid but by wiping with a cleaner-soaked cloth. 3. Take care and prevent any flux, cleaning liquid, or desiccant from entering the inside of the sensor or getting into the vent hole. 4. After the pressure ports and the terminals are mechanically positioned so that no mechanical force is applied to them, solder the terminals to the PCB.
6. Recommended fittings for M5 female screws connecting tubes
Q. We want to connect a pressure sensor to its tube using an M5 female screw. What attachment do you recommend?	Answer We want to connect a pressure sensor to its tube using an M5 female screw. What attachment do you recommend? -- Answer -- For our recommended fittings for connecting pressure sensors to urethane/nylon tubes, refer to the following table. Manufacturer Fitting type Tube outer diameter(mm) φ4 (2.5×4) φ6 (4×6) Koganei Co., Ltd. Quick fitting TS4-M5M TS6-M5M TAC fitting BF4 BF6 Nihon pisco co. ltd Tube fitting PC4-M5 PC6-M5 Tube fitting PC4-M5M PC6-M5M Tube fitting minimal LC-0425-M5 LC-0640-M5 ※If you have any questions about the specs of the fittings, such as detailed dimensions, directly ask the manufacturers shown in the table.
7. Recommended tubes for quick fittings
Q. What tubes do you recommend for use with the quick fittings?	Answer What tubes do you recommend for use with the quick fittings? -- Answer -- For our recommended urethane/nylon tubes, refer to the following table. Manufacturer's name Tube type Tube outer diameter (mm) φ4 (4×2.5) φ6 (6×4) Koganei Co., Ltd. Nylon tube N4B N6B Urethane tube U4 U6 Nihon pisco co. ltd Nylon tube NA0425 NA0640 Urethane tube UB0425 UB0640 ※If you have any questions about the specifications for the tubes, such as maximum operating pressure, directly ask the manufacturers shown in the table.
8. How to installate to piping (Tightening torque)
Q. What tightening torques do you recommend for tapered screw types?	Answer What tightening torques do you recommend for tapered screw types? -- Answer -- Take into consideration such factors as the material of the fitting to set the optimum value. (Fig.) Screw shape Tightening torque(N·m) R 1/8 7 ~ 9 R 1/4 12 ~ 14 R 3/8 22 ~ 24 M 5 1.0 ~ 1.5
9. Effect of vertical to horizontal installation position
Q. The dual-diaphragm pressure sensor we use varies in output depending on whether the pressure port is turned downward or sideways. Does this mean the sensor is out of order?	Answer The dual-diaphragm pressure sensor we use varies in output depending on whether the pressure port is turned downward or sideways. Does this mean the sensor is out of order? -- Answer -- Our dual-diaphragm pressure transducer contains sealed-in silicone oil, and its output varies when its sensor element detects the weight of the silicone oil. If stable in its installed position, the transducer shows constant output. The influence of the installed position varies depending on the model and pressure range of the transducer. Refer to the brochure for details. e.g. Internal structure of P-8300 pressure transducer Part name Material ①Sealed liquid Silicone oil ②Sensor chip Silicone ③Stainless steel diaphragm SUS316L ④Compensation resistor board Ceramic ⑤Vent hole (Gauge type only) Iron+gold-plated ⑥Pressure port SUS316L ⑦Terminal pin Copper+gold-plated
10. Stability after power applied
Q. According to the Common Notes, a warm-up time of about 10 minutes after power-on allows more accurate measurement. How much does the output voltage [V] fluctuate during the 10 minutes after power-on? We also want to know whether the output voltage changes linearly or not.	Answer According to the Common Notes, a warm-up time of about 10 minutes after power-on allows more accurate measurement. How much does the output voltage [V] fluctuate during the 10 minutes after power-on? We also want to know whether the output voltage changes linearly or not. -- Answer -- After power-on, the zero point shifts and stabilizes in about 10 minutes, as shown in the chart below. Hence, a warm-up time of about 10 minutes after power-on ensures more stable output and hence allows more accurate measurement. The chart below is for reference only. Fig.) Stability of zero point after power on（Product ratio of our company） ※Refer to the chart（The direction and magnitude of shifting vary depending on the product.)
11. Products selection suitable for using high vacuum
Q. Introduced PA-850-102A-NR2 to monitor the pressure inside the vacuum chamber. Our process requires pressure reduction to an absolute pressure of approx. 0 kPa. The brochure specifies a lower limit of operating vacuum of 1.3 kPa abs. Why is it unusable beyond this value? Recommend pressure sensors usable beyond the value.	Answer We have adopted the PA-850-102A-NR2 to monitor the internal pressure of a vacuum chamber. Our process requires pressure reduction to an absolute pressure of approx. 0 kPa. The brochure specifies a lower limit of operating vacuum of 1.3 kPa abs. Why is it unusable beyond this value? Recommend pressure sensors usable beyond the value. -- Answer -- Long-term use in a high vacuum may lead to a shift in the output of our dual-diaphragm pressure transducers because of air trapped within the silicone oil. Therefore, a lower limit of operating vacuum of 1.3 kPa abs is specified. We offer silicone oil-free, thin-film element pressure transducers as high vacuum-compatible products. See the table on the right side below: A. Double diaphragm(Oil-enclosured) type Series name Pressure lower limit P-8300, P-8305, P-8505, PA-750, PA-758, PA-800, PA-830, PA-838, PA-838-D, PA-840, PA-848, PA-850, PA-858, PS8, PS83, PS85, PG-35,PG-75, PG-208, PG-100B 1.3 kPa abs. B. Thin film type(High vacuum compatible) Series name PA-920S, PA-928S, PA-930, PA-930-A, PS91, PG-20, PG-35L Product Lineup of Thin-film Pressure Sensors click here.
12. About operating temperature range of medium
Q. What is the liquid temperature range applicable to the PG-35? Although we are currently using room-temperature water, we want to use heated water and hence have to know the liquid temperature range.	Answer What is the liquid temperature range applicable to the PG-35? Although we are currently using room-temperature water, we want to use heated water and hence have to know the liquid temperature range. -- Answer -- The liquid temperature range applicable to the PG-35 is the same as the operating temperature range of -10°C to 50°C. The operating temperature range varies depending on the model. Refer to the Product Guide for details.（PDF） We may be able to recommend a wider temperature range depending on the applicable use conditions. Check with our sales office, sales agent, or authorized sales distributor in your area. Click here to check pressure sensor products. Pressure sensors product guide
13. Effect of accuracies by ambient temperature
Q. How come the PG-100B has two different system accuracies, one being ±0.5%F.S. ±2 digits and the other being ±1.0%F.S. ±2 digits? Besides, what does "±2 digits" mean?	Answer How come the PG-100B has two different system accuracies, one being ± 0.5% F.S. ± 2 digits and the other being ± 1.0% F.S. ± 2 digits? Besides, what does "± 2 digits" mean? -- Answer -- While ± 0.5% F.S. ± 2 digits (25°C ± 5°C) is the level of accuracy within the rated pressure range at a constant ambient temperature of 25°C, ± 1.0% F.S. ± 2 digits (25°C ± 25°C) is the level of accuracy within the rated pressure range under ambient temperature ranging from 0 to 50°C. The value ± 2 digits means that the lowest digit of the reading includes ± 2 digits' worth of errors.
14. Rated pressure range / Max. pressure / Break pressure
Q. What does the rated pressure range and maximum pressure in the specification mean? Will the sensor be broken if the burst pressure value is exceeded?	Answer What does the rated pressure range and maximum pressure in the specification mean? Will the sensor be broken if the burst pressure value is exceeded? -- Answer -- The rated pressure range is a range of pressure by which we guarantee the specifications of the pressure sensor. The maximum pressure is the largest value of pressure that you can apply to the pressure sensor. After the application of the maximum pressure beyond the rated pressure, the specifications are guaranteed within the rated pressure. Note, however, that the offset voltage, the zero voltage, and the zero current may change. The "burst pressure" means the pressure value at which electrical or mechanical destruction occurs to the pressure sensor. Caution is advised in this case because the pressure medium under measurement is very likely to leak out.
15. How to purchase lithium batteries for PG-100
Q. The replacement battery specified for the PG-100 manometer is a lithium battery 3.6 VDC. The battery originally supplied with the PG-100 is one manufactured by Toshiba and bearing the model number ER6VM/3.6, which cannot be found on Toshiba's website, although ER6V P3.6 is found there. Is it OK to use the latter instead?	Answer The replacement battery specified for the PG-100 manometer is a lithium battery 3.6 VDC. The battery originally supplied with the PG-100 is one manufactured by Toshiba and bearing the model number ER6VM/3.6, which cannot be found on Toshiba's website, although ER6V P3.6 is found there. Is it OK to use the latter instead? -- Answer -- The only lithium battery usable with the PG-100 is ER6VM/3.6, manufactured by Toshiba Lifestyle Products & Services Corporation. ER6VM/3.6 is not available off the shelf. To purchase it, contact our sales office, sales agent, or authorized distributor in your area and inform of the model name “Lithium Battery (for PG)”. The used battery must not be disassembled, short-circuited, recharged, thrown into a fire, heated, or tampered with in any other way. Dispose of the used lithium battery according to the regulations applicable to your area. When not to be used for a long period, remove the battery from the manometer and store it in a dry, cool place.
16. Product lineup in accordance with UL991
Q. We are considering using a pressure sensor for a semiconductor manufacturing machine. Are UL991-compliant ones available from you?	Answer We are considering using a pressure sensor for a semiconductor manufacturing machine. Are UL991-compliant ones available from you? -- Answer -- Yes. Our product lineup Pressure gauge PG-20,a pressure gauge installable into integrated gas units. Pressure gauge PG-20 series Pressure gauge PG-20 series ※Click here for details of pressure gauge PG-20 series
17. How to solve E2 ERRORs in pressure gauges
Q. We restarted a PG-75 for the first time after long-term non-use. Its zero adjustment resulted in an "E2 Error" message. How should this be dealt with?	Answer We restarted a PG-75 for the first time after long-term non-use. Its zero adjustment resulted in an "E2 Error" message. How should this be dealt with? -- Answer -- The "E2 Error" message occurs as a result of zero adjustment performed with a residual pressure exceeding ±10%. To undo the error, press the M key. After venting the pressure to atmosphere, perform zero adjustment again. PG-75 instruction manual
18. Effects of the use of not specified power supplies
Q. According to its specifications, the P-3000S is driven with a standard constant current of 1.5mA. Is there any problem when it is driven with a constant voltage of 5 V? Besides, what will become of the accuracy of linearity and that of the temperature characteristics when a 1mA current is set for a constant current drive?	Answer According to its specifications, the P-3000S is driven with a standard constant current of 1.5 mA. Is there any problem when it is driven with a constant voltage of 5 V? Besides, what will become of the accuracy of linearity and that of the temperature characteristics when a 1-mA current is set for a constant current drive? -- Answer -- The P-3000S is a high-precision pressure sensor with a built-in temperature compensation circuit. Temperature compensation is driven by a power supply with a constant current of 1.5 mA to optimize the temperature within a range of 0°C to 50°C. The driving power supply can still work with a constant voltage of 5 V, which, however, results in poor temperature characteristics. With a constant current of 1 mA, the output voltage will decrease, resulting in poor temperature characteristics.
19. How to solve Zero Point ERRORs in pressure gauges
Q. The PG-100 handy manometer we use reads "-00.3" at power-on. The normal reading should be either "00.0" or "00.1." Is our PG-100 out of order?	Answer The PG-100 handy manometer we use reads "-00.3" at power-on. The normal reading should be either "00.0" or "00.1." Is our PG-100 out of order? -- Answer --   The zero reading of the PG-100 may shift depending on external factors, such as a change in the ambient temperature. The PG-100 has a zero adjustment trimmer at its top. Adjust the trimmer with a precision screwdriver.In addition, the zero-point adjustment of the new dry cell-powered type is a digital type that can be operated by a one-touch button. 1.  Current products: Dry battery driven (2 types) PG-100N Instruction manual PG-100B Instruction manual 2.  Discon product: Lithium battery driven PG-100 Instruction manual Click here for more information about handheld digital manometers.
20. Batteries replacement notice of Manometers
Q. Is it normal that the reading by the PG-100 manometer appears thin when its battery is running low? Does a dying battery result in a reading lower than the actual pressure? Is there any method we can check with as the reference for the time to replace the battery?	Answer Is it normal that the reading by the PG-100 manometer appears thin when its battery is running low? Does a dying battery result in a reading lower than the actual pressure? Is there any method we can check with as the reference for the time to replace the battery? -- Answer --   When the battery is running low, "LOBAT" appears in the upper left part of the LCD to prompt the user to replace the battery. 1.  Dry battery driven (2 types) PG-100N Instruction manual PG-100B Instruction manual 2.  Lithium battery driven PG-100 Instruction manual Click here for more information about handheld digital manometers.
21. About elements and materials of pressure sensors
Q. We have adopted the PG-35 pressure gauge as the atmospheric pressure detector for the vacuum equipment we manufacture. The specifications for the equipment of an end-user who has placed an inquiry for our vacuum equipment require that the atmospheric pressure sensor to be used shall be a semiconductor sensor with a diaphragm made of stainless steel. Does the PG-35 meet this requirement?	Answer We have adopted the PG-35 pressure gauge as the atmospheric pressure detector for the vacuum equipment we manufacture. The specifications for the equipment of an end-user who has placed an inquiry for our vacuum equipment require that the atmospheric pressure sensor to be used shall be a semiconductor sensor with a diaphragm made of stainless steel. Does the PG-35 meet this requirement? -- Answer -- The liquid contact part of the PG-35 is made of SUS 316L stainless steel and meets the requirement. Note, however, that the sensor module of the PG-35 is a dual-diaphragm pressure transducer with sealed-in silicone oil. Use under high vacuum may cause the air entrapped in the silicone oil to bubble, resulting in a shift in the zero voltage. For use under a pressure of 1.3 kPa abs or lower, we recommend the PG-35L, a silicone oil-free, thin-film element pressure gauge. Click here to download the brochure for the PG-35L. A. Double diaphragm(Oil-enclosured) type Series name Pressure lower limit P-8300, P-8305, P-8505, PA-750, PA-758, PA-800, PA-830, PA-838, PA-838-D, PA-840, PA-848, PA-850, PA-858, PS8, PS83, PS85, PG-35,PG-75, PG-208, PG-100B 1.3 kPa abs. B. Thin film type(High vacuum compatible) Series name PA-920S, PA-928S, PA-930, PA-930-A, PS91, PG-20, PG-35L Product Lineup of Thin-film Pressure Sensors click here.
22. Manometers selection for organic solvent medium
Q. We want to use a PG-100-102A at hand to measure a fluid containing a diluted organic solvent. Is this possible?	Answer We want to use a PG-100-102A at hand to measure a fluid containing a diluted organic solvent. Is this possible? -- Answer -- The medium for use with the PG-100-102A is a noncorrosive gas (moisture-free air or inert gas). For users intending to measure the pressure of a fluid containing an organic solvent, we recommend the PG-100B-102A with a pressure receiver made of SUS 316L stainless steel. click here for details of handheld digital manometer PG-100B
23. Use at high altitudes / Kind of pressure references
Q. We are considering using a PS6-102G-NAR in a location at an altitude of 1,000 [m]. Can it be used in this way?	Answer We are considering using a PS6-102G-NAR in a location at an altitude of 1,000 [m]. Can it be used in this way? -- Answer -- Yes, it can. The PS6-102R-NAR pressure switch reads gauge pressure using atmospheric pressure as its reference pressure (0 kPa), and its altitude standard at the height of 1,000m is atmospheric pressure. Pressure indication method
24. Out of Production
Q. What is the discontinuation information for the pressure sensor?	Answer What is the discontinuation information for the pressure sensor? -- Answer -- Information on discontinued products and alternative products is posted on the company's HP product information page. Information about discontinued products, Click here.
25. How to operate the settings of Pressure gauge PG-30/PG-35？
Q. Can you tell me the panel settings and operation steps of the pressure gauge PG-35l purchased? Is there any explanatory material that beginners can understand?	Answer Can you tell me the panel settings and operation steps of the pressure gauge PG-35l purchased? Is there any explanatory material that beginners can understand? -- Answer -- The various operation panel setting modes of the pressure display gauge PG-30/35 series are explained in a simple and easy-to-understand manner in the YouTube video. Click the play button to watch YouTube video. We have videos available for each setting for PG-30/PG-35. Initial setting mode   Pressure setting mode Zero adjust, Non-display, Panel protection   PG-30/35 series instruction manual

2. Documents and Certificates

3. Maintenance and Calibration