Vaisala PDT101 and PDT102 Differential Pressure Transmitters
The Vaisala PDT101 and PDT102 differential pressure transmitters are designed to measure very small pressure differences between rooms, corridors, airlocks, ducts and air-handling components.
Accurate differential-pressure monitoring helps confirm the intended direction of airflow. This is essential for maintaining cleanroom pressure cascades, protecting isolation areas, preventing contamination migration and identifying blocked filters or abnormal fan performance.
Both transmitters provide analog outputs for connection to building-management systems, programmable controllers, data loggers and environmental monitoring systems. They can also be incorporated into the Vaisala viewLinc Continuous Monitoring System for documented monitoring, alarming and reporting in regulated facilities.
Which Model Should You Choose?
| Selection Requirement | Recommended Model | Reason |
|---|
| General critical-room monitoring |
PDT101 bidirectional |
Compact transmitter with ±60 Pa or ±125 Pa ranges and 0.40% span accuracy |
| Highest-accuracy cleanroom monitoring |
PDT102 |
Accuracy options of 0.25% or 0.50% of span for demanding regulated applications |
| AHU fan or filter monitoring |
PDT101 unidirectional |
0–500 Pa range designed for pressure drop across fans and filters |
| In-place calibration without disconnecting tubes |
PDT102 with process valve actuator and test jacks |
Supports online checking and calibration with minimal disruption |
| Compact wall, panel or DIN-rail mounting |
PDT101 |
Small, lightweight enclosure with flexible mounting methods |
| Ultrathin DIN-rail installation |
PDT102 |
Narrow 22.6 mm profile conserves cabinet space |
Why Monitor Differential Pressure?
- Pressure Cascades: Confirms that air flows from cleaner spaces toward less-clean areas.
- Contamination Control: Helps prevent particles, microorganisms or hazardous substances from moving between controlled zones.
- Room-Pressure Alarms: Provides a signal for warning personnel when pressure moves outside the required limits.
- Isolation-Room Safety: Supports positive- or negative-pressure room strategies according to the application.
- Filter Monitoring: Increasing pressure drop can indicate filter loading or blockage.
- Fan Performance: Differential pressure can help verify air-handler or ventilation-fan operation.
- Documented Compliance: Continuous monitoring provides historical evidence for quality review and audits.
Vaisala PDT101 Differential Pressure Transmitter
The PDT101 is the flexible choice for critical environments and air-handling systems. Bidirectional models measure positive and negative pressure around zero for room-to-room monitoring, while unidirectional models measure pressure drop across fans, filters and other HVAC components.
- Bidirectional Ranges: ±60 Pa, ±125 Pa, ±0.25 inH₂O or ±0.5 inH₂O.
- Unidirectional Ranges: 0–500 Pa or 0–2 inH₂O.
- Accuracy: 0.40% of span for bidirectional models and 1% of span for unidirectional models.
- Output Choices: Two-wire 4–20 mA or three-wire voltage output.
- Mounting: Wall, panel or DIN rail.
- Front Adjustment: Accessible zero and span potentiometers.
- Status Indication: Front LED for quick power-status checking.
PDT101 Models and Ranges
| Model Family | Measurement Range | Output | Typical Use |
|---|
| PDT101-P4C |
±60 Pa |
4–20 mA |
Critical-room and cleanroom pressure monitoring |
| PDT101-P4V |
±60 Pa |
0–5 V |
Critical-room monitoring with voltage input |
| PDT101-P4C2 |
±125 Pa |
4–20 mA |
Wider bidirectional room-pressure range |
| PDT101-P4V2 |
±125 Pa |
0–5 V |
Wider bidirectional range with voltage output |
| PDT101-P10C |
0–500 Pa |
4–20 mA |
AHU fan and filter differential pressure |
| PDT101-P10V |
0–500 Pa |
0–10 V |
AHU fan and filter monitoring with voltage output |
Equivalent inch-water-column variants are available. Confirm the required engineering unit, range, output and calibration-certificate requirement when ordering.
Calibration-certificate note: The standard PDT101 models are supplied with calibration traceable to SI units. Certain PDT101 model codes ending in “x” do not include a calibration certificate; specify the requirement before ordering.
PDT101 Measurement Specifications
| Measurement Specification | Performance |
|---|
| Bidirectional Accuracy |
0.40% of span |
| Unidirectional Accuracy |
1% of span |
| Long-Term Stability |
±0.25% of span per year or better |
| Response Time |
250 ms from 10% to 90% |
| Warm-Up Time |
15 seconds |
| Compensated Temperature Range |
+2 to +54 °C |
| Proof Pressure |
1.0 bar |
| Burst and Static Pressure |
1.7 bar |
Vaisala PDT102 High-Accuracy Differential Pressure Transmitter
The PDT102 is designed primarily for life-science and high-technology cleanrooms where very high accuracy, sensitivity and repeatability are required. Its micromachined MEMS silicon diaphragm provides stable ultra-low-pressure measurement.
- High Accuracy: Select 0.25% or 0.50% of span.
- Bidirectional Range: ±50 Pa or ±0.25 inH₂O.
- Calibration Certificate: Calibration traceable to SI units is supplied.
- Online Test Option: Optional process valve actuator and front test jacks support checking without disturbing the process tubes.
- Ultrathin Housing: Approximately 22.6 mm deep for efficient DIN-rail installation.
- Output Choices: Two-wire 4–20 mA or three-wire 0–5 V.
- Front Adjustment: Zero and span potentiometers remain accessible after installation.
PDT102 Measurement Specifications
| Measurement Specification | Performance |
|---|
| Bidirectional Range |
±50 Pa or ±0.25 inH₂O |
| Accuracy Options |
0.25% or 0.50% of span |
| Repeatability |
0.03% for 0.25%-accuracy model; 0.05% for 0.50%-accuracy model |
| Electrical Resolution |
1 × 10−4 of span |
| Long-Term Stability |
±0.25% of span per year or better |
| Response Time |
250 ms from 10% to 90% |
| Warm-Up Time |
15 seconds |
| Compensated Temperature Range |
+2 to +57 °C |
| Proof Pressure |
0.7 bar |
| Burst and Static Pressure |
1.7 bar |
Electrical Output Selection
| Output | Wiring | Recommended Use |
|---|
| 4–20 mA |
Two-wire loop powered |
Long cable runs, industrial controllers, data loggers and monitoring cabinets |
| 0–5 V |
Three-wire |
Controllers and acquisition systems with compatible voltage inputs |
| 0–10 V |
Three-wire; PDT101 unidirectional models |
Building-management and HVAC controllers using 0–10 V inputs |
Electrical and Mechanical Comparison
| Specification | PDT101 | PDT102 |
|---|
| Operating Voltage |
12–36 V DC for 4–20 mA; voltage versions also support specified DC or 24 V AC supplies |
12–36 V DC |
| Process Connection |
¼-inch barbed brass fittings |
⅛-inch NPT female |
| Measured Medium |
Clean, dry air and non-conducting, non-corrosive gases |
Clean, dry air and non-conducting, non-corrosive gases |
| Mounting |
Wall or EN 50022 DIN rail |
EN 50022, EN 50035 or EN 50045 DIN rail |
| Protection Rating |
IP40 |
IP30 |
| Operating Temperature |
−18 to +70 °C |
−29 to +70 °C |
| Storage Temperature |
−40 to +82 °C |
−40 to +82 °C |
| Approximate Weight |
0.07 kg |
0.16 kg |
Cleanroom Pressure-Cascade Monitoring
A cleanroom pressure cascade uses controlled pressure differences to establish the required airflow direction between adjoining spaces. A transmitter is typically connected across a wall, door or room boundary, with the high- and low-pressure tubes routed to representative pressure locations.
| Monitoring Point | Purpose |
|---|
| Cleanroom to Corridor |
Confirms positive pressure that helps keep unfiltered corridor air outside the cleanroom |
| Airlock to Adjacent Room |
Verifies the designed step in a multi-room pressure cascade |
| Negative Isolation Room |
Confirms inward airflow to help contain hazardous or infectious material |
| Positive Protective Room |
Confirms outward airflow to protect sensitive products or occupants |
| Filter or Fan |
Measures pressure drop for condition and performance monitoring |
Integration with Vaisala viewLinc
PDT101 and PDT102 analog signals can be integrated with the Vaisala viewLinc Continuous Monitoring System through a compatible input device or the Vaisala CAB100 Industrial Cabinet.
- Continuous Records: Differential-pressure measurements are stored with other environmental data.
- Threshold Alarms: Responsible personnel can be notified when room pressure exceeds configured limits.
- Audit Trails: System activities and alarm acknowledgements can be documented.
- Historical Reports: Pressure trends can support investigations, quality review and inspections.
- Multi-Parameter Monitoring: Pressure, temperature, humidity, CO₂ and other parameters can be managed in one system.
PDT101 and PDT102 Integration with CAB100
The Vaisala CAB100 Industrial Cabinet provides a centralised and organised method of connecting differential-pressure measurements to viewLinc. It can contain selected pressure transmitters, analog-input channels, power components and communication interfaces in a preconfigured enclosure.
This arrangement is particularly useful in pharmaceutical plants, biotechnology facilities, laboratories and semiconductor cleanrooms where several room-pressure measurements must be installed, powered, commissioned and maintained as one monitoring system.
| System Component | Function |
|---|
| PDT101 or PDT102 |
Measures the differential pressure between the high- and low-pressure locations |
| 4–20 mA or Voltage Signal |
Transfers the scaled differential-pressure measurement to a compatible CAB100 input configuration |
| CAB100 Cabinet |
Centralises selected transmitters, analog inputs, power equipment, communication devices and field wiring |
| viewLinc Enterprise Server |
Stores measurement records and provides displays, threshold alarms, reports and audit-trail functions |
CAB100 Configuration Options for Differential Pressure
| Project Requirement | Recommended CAB100 Approach |
|---|
| Centralised PDT101 installation |
Select a CAB100 PDT101 configuration according to the required number of pressure channels and cabinet capacity |
| Remote PDT101 or PDT102 transmitter |
Use a compatible CAB100 analog-input configuration after confirming signal type, scaling and power requirements |
| Pressure plus other analog measurements |
Select a CAB100 analog-input or suitable mixed configuration reviewed against the complete channel requirement |
| Higher channel quantity |
Use the larger CAB100B or multiple cabinets according to the system architecture |
| Regulated cleanroom project |
Define pressure ranges, engineering units, alarm thresholds, calibration requirements and viewLinc validation documentation before configuration |
Configuration requirement: CAB100 is supplied in application-specific configurations. Confirm the transmitter quantity, signal type, range, scaling, power supply, cable distance and required viewLinc architecture before ordering. Not every CAB100 configuration accepts every transmitter combination.
Benefits of a CAB100-Based Pressure Monitoring System
- Centralised Installation: Multiple differential-pressure channels can be organised in one defined cabinet location.
- Simplified Field Wiring: Preconfigured internal components reduce site assembly and make termination easier to inspect.
- Consistent System Architecture: Pressure measurements can be combined with temperature, humidity and other environmental parameters in viewLinc.
- Easier Commissioning: Channel ranges, signal scaling and monitoring points can be documented systematically.
- Service Accessibility: Centralised components simplify inspection, calibration planning and future maintenance.
- Scalable Monitoring: CAB100A, CAB100B or multiple cabinets can be selected according to the project size.
View the Vaisala CAB100 Industrial Cabinet
Related Vaisala Monitoring Components
Installation and Commissioning Guidance
- Confirm the expected positive and negative pressure limits before selecting the measurement range.
- Connect the higher-pressure space to the high port and the lower-pressure space to the low port.
- Keep tubing runs as short and direct as practical, without sharp bends, leaks or trapped moisture.
- Use the specified clean, dry and non-corrosive gas medium only.
- Mount the transmitter in the same orientation used for calibration whenever possible.
- Allow the specified warm-up period before performing zero or span verification.
- Perform a zero check after installation and according to the facility calibration programme.
- For regulated systems, document the selected range, alarm limits, calibration results and test procedure.
Common Applications
- Pharmaceutical and biotechnology cleanrooms
- Medical-device manufacturing
- Semiconductor and electronics production
- Hospital isolation and protective rooms
- Laboratories and controlled research environments
- Data-centre room and airflow monitoring
- Air-handling unit fan and filter monitoring
- GxP-regulated production and storage facilities
Vaisala PDT101 and PDT102 Supplier in Malaysia
Seacom Process Instruments supplies and supports the Vaisala PDT101 and PDT102 differential pressure transmitters in Malaysia for cleanrooms, isolation rooms, pharmaceutical facilities, laboratories, semiconductor production, data centres and air-handling systems.
Our team can assist with model selection, pressure range, output type, tubing arrangement, mounting, CAB100 cabinet configuration, viewLinc integration, commissioning, calibration and GxP documentation.
Contact Seacom for PDT101 or PDT102 Selection
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PDT101 Catalogue
- Differential Pressure Transmitter PDT101
(346.56k)
