Digital pressure gauges are essential tools for accurately measuring and monitoring pressure changes in industrial and laboratory environments. They improve measurement accuracy and also display values in real time that facilitate operation and data recording. This article will basically guide you through the working principles, features and applications of digital pressure gauges.

What is a Digital Pressure Gauge?

A digital pressure gauge is an electronic device used to measure the pressure of gases or liquids. Unlike traditional analog pressure gauges, digital pressure gauges present pressure values ​​on a digital display that makes readings more intuitive and reducing human error.

How Does a Digital Pressure Gauge Work?

The working principle of a digital pressure gauge is based on a pressure sensor. The pressure sensor converts physical pressure into a weak electrical signal. After amplification and analog-to-digital conversion, a microprocessor performs precise calculations, compensation and processing that ultimately display the result in digital form and enable a variety of intelligent functions.

Features and Advantages of Digital Pressure Gauges

High Precision and High Resolution

• High Precision: Ordinary digital pressure gauges achieve an accuracy of ±0.5% FS (full scale) with mid-to-high-end products reaching ±0.25% FS, ±0.1% FS or even higher. Ordinary mechanical gauges typically only achieve ±1.6% FS.
• High Resolution: Capable of displaying extremely small pressure changes. For example a gauge with a 1MPa range can easily display down to 0.001MPa (1kPa), while something difficult to achieve with a mechanical gauge relying on pointer estimation.

Superior Readability and User Experience

• No Parallax: Digital displays completely eliminate reading errors caused by different viewing angles in mechanical gauges.
• Intuitive Reading: Directly displays numbers to eliminate the need to distinguish which scale the pointer is pointing to, as with mechanical gauges that greatly reduce the possibility of human misreading.
• Flexible Unit Switching: Allows one-button switching between multiple pressure units (such as MPa, bar, psi, kgf/cm²) without conversion that make it extremely convenient.

Superior Stability and Reliability

• Vibration and Shock Resistance: With no internal precision mechanical moving parts, the pointer will not jitter under vibration and shock environments that ensure stable readings and a longer lifespan.
• No Mechanical Wear: Its performance will not degrade due to mechanical wear over time or frequent use.
• Strong Overload Capacity: Many sensors especially ceramic sensors have excellent overpressure resistance.

Rich Intelligent Functions

• Peak Recording: Records and displays the maximum and minimum values during measurement that are crucial for analyzing system pressure shocks and fluctuations.
• Zeroing/Relative Value Measurement: Can be zeroed at any point for relative pressure measurement.
• Automatic Shutdown: Saves power and extends battery life.
• Alarm Output: Upper and lower alarm limits can be set and control signals can be output via relays to achieve automatic control or safety alarms.
• Data Recording and Output: Equipped with communication interfaces such as RS485, RS232, 4-20mA analog output, Bluetooth/Wi-Fi, etc., data can be transmitted to PLC, DCS or computer systems for data acquisition and remote monitoring.

Enhanced Environmental Adaptability

• Temperature Compensation: The microprocessor can compensate for changes in ambient temperature to maintain high accuracy over a wide temperature range.
• Easy Sealing: Electronic components are easier to seal completely that achieve higher protection levels (such as IP65, IP67) and provide excellent dust and water resistance.

What Types of Digital Pressure Gauges?

Digital pressure gauges are mainly divided into digital dial gauge and digital pressure indicators. A digital dial gauge is a type of DPG that resemble a traditional dial gauge in appearance with a process connection and a round case with a display screen. Digital pressure indicators are typically provided in desktop or rack-mount chassis.

Feature	Digital Dial Gauge	Digital Pressure Indicator
Core Function	High-precision local display	Display + Remote Signal Transmission + Control
Output Signal	Normally none	Available with (4-20mA, RS485, relays, etc.)
Role	Replace mechanical watches and optimize readings	Industrial automation measurement and control unit
Power Supply	Commonly battery power	Commonly external power supply

Applications

Digital pressure gauges are multi-functional instruments widely used in various industries and applications, including:

• Industrial Processes: Monitoring and controlling pressure in manufacturing and processing plants.
• Laboratory: Precise pressure measurement in scientific research and experiments.
• Hydraulics and Pneumatics: Ensuring accurate pressure readings for hydraulic systems and pneumatic controls.
• HVAC Systems: Measuring and regulating pressure in heating, ventilation and air conditioning systems.
• Automotive Industry: Testing and monitoring pressure in automotive components and systems.

How to maintain a digital pressure gauge?

Routine Maintenance

Visual Inspection

• Cleaning: Regularly wipe the casing and display with a soft, dry cloth. If it gets heavily greasy, wipe it with a cloth dampened with a small amount of water or neutral detergent. Never use strong chemical solvents such as benzene, alcohol or gasoline.Because these may damage the casing or screen.
• Damage Inspection: Inspect the casing, glass or screen for cracks, breaks or severe scratches that  ensure its seal is intact.

Operating Status Check

• Display Check: Confirm that all segments, numbers and symbols on the display screen are clearly and normally displayed without missing strokes or dimness after powering on.
• Zero Point Check: After turning off the equipment and adjusting the pressure to zero, you should observe whether the instrument display shows zero or is within its allowable zero-point error range. If there is significant zero-point drift, calibration is required.
• Connection Check: Check for leaks at pressure connection interfaces (it can be checked by applying soapy water). Check that cable joints are secure and free from corrosion or loosening.

Regular Maintenance and Calibration

Regular maintenance and calibration are planned and more in-depth maintenance that are important for ensuring accuracy.

Regular Calibration

Even if the instrument is not damaged, its accuracy will drift over time. Regular calibration is the only way to ensure the reliability of measurement data.

The calibration frequency depends on usage frequency, environmental conditions and importance. Critical process points may require calibration every 3-6 months, while general applications may require calibration every 6-12 months. The calibration cycle must be included in the company’s metrology management system.

Use a standard pressure source (such as a piston gauge or high-precision digital pressure calibrator) with an accuracy class 3-10 times higher than the instrument being calibrated to perform up and down stroke calibration and compare the indicated error.

Power Supply and Signal Check (for instruments with output functions)

• Power Supply: Use a multimeter to check if the power supply voltage is within the instrument’s required range (e.g., 24V DC ± 10%). Unstable or excessively high voltage will damage the instrument.
• Output Signal: Under known pressure, use a multimeter or process calibrator to measure the output current (e.g., 4-20mA) to verify if it corresponds to the displayed value, thus verifying its output accuracy.

Internal Inspection (if necessary and available)

If the instrument is maintained by a professional in a laboratory, the casing can be opened (take precautions against static electricity) to check for moisture, corrosion or signs of burnt components inside.

Storage and Maintenance During Long-Term Non-Use

The instrument should be stored in a clean, dry and well-ventilated environment free of corrosive gases.

The storage temperature should be within the range specified in the instrument’s instruction manual that avoid extreme high or low temperatures.

If a battery-powered instrument is not used for an extended period, the battery should be removed to prevent leakage and corrosion of the internal circuitry.

Common Faults and Troubleshooting

When an instrument malfunctions, troubleshooting can be done using the following table:

Fault	Possible Reasons	Check steps
No display	Power supply not connected or damaged	Check the power cord and switch
	Battery depleted	Replacement battery
	Internal fuse blows	Check and replace the fuse.
	The instrument is severely damaged.	Return to factory for repair
Unstable or fluctuating display values	Sensors or circuits are damp	Drying or return to factory for repair
	Power supply fluctuations or interference	Use a regulated power supply and check the grounding.
	The pressure source itself is unstable (e.g., pump pulsation).	Add a damping valve before the pressure port.
	Loose wiring	Tighten all terminals.
Large display error/Inaccuracy	Uncalibrated	Recalibrate
	Sensor overload damage	Check for overpressure; return to factory for repair.
	Zero Drift	Zero-point calibration
The display is showing an abnormal output signal.	Output loop wiring error or open circuit	Check wiring and loop resistance
	Excessive load resistance	Ensure the load is within the allowable range (e.g., 4-20mA output, load ≤750Ω).
	Output module damaged	Return to factory for repair

Different models of instruments may have specific maintenance requirements. Please be sure to carefully read the instruction manual provided by the manufacturer. Following the above maintenance procedures can greatly extend the service life of the digital pressure gauge, ensure the accuracy and reliability of its measurement data and provide assurance for production safety and product quality.

Why Choose ZJSIHEGF Digital Pressure Gauges?

ZJSIHEGF digital pressure gauges are widely popular in the market for their high precision, stability and durability. Our products utilize advanced sensing technology to provide more accurate and reliable pressure measurement results. Furthermore, the multi-functional design of ZJSIHEGF digital pressure gauges makes them suitable for various industrial and scientific research applications that make them the first choice for many users.

Through the above introduction, you can gain a clearer understanding of the working principle, application areas and how to maintain digital pressure gauges. If you are looking for high-performance digital pressure gauges, ZJSIHEGF is undoubtedly a brand worth considering.