The 22ADP-584A is a Belimo active 24V differential pressure transducer for air, with a medium pressure range of -0.4 to 10 inch WC (-100 to 2500 Pa) and eight DIP-switch-selectable measuring sub-ranges. One SKU adapts to multiple applications without re-specifying a range variant. The sensor uses a piezo measuring element with ±0.02 inch WC accuracy below 2 inch WC and ±0.04 inch WC above. Two active analog outputs deliver pressure and volumetric flow - switch-selectable between 0-5V, 0-10V, and 4-20 mA. Analog-only variant: no bus communication. The auto-zero feature automatically compensates for sensor drift at configurable intervals - critical for low-range applications. The orange polycarbonate housing is rated NEMA 4X / IP65 with UL 2043 plenum compliance. A 1/2" NPT conduit adapter, mounting plate, and duct connector kit ship in the box.
HVAC differential pressure monitoring in the -0.4 to 10 inch WC range: filter status (clogged-filter alarms at 0.5-1 inch WC delta-P), fan V-belt slippage detection, smoke/fire damper position verification, and general duct static pressure for pressure-independent VAV control. Same range, different configurations: 22ADP-584 ($487), 22ADP-584B ($812). For higher pressure (up to 28 inch WC), see the 22ADP-556 family. For lower / more sensitive (-0.6 to 1 inch WC, cleanroom/lab), see the 22ADP-55Q family.
An internal solenoid valve periodically isolates the sensor from the pressure ports and re-zeros the reading automatically at a configurable interval. This eliminates the typical drift that affects piezo sensors at low pressure ranges, removing the need for frequent manual zero-point calibration. Especially valuable at the most sensitive sub-ranges (S5-S7) where a small offset translates to a large percentage error.
After initial commissioning, perform manual zero-point calibration to set the sensor's reference offset. Recommended interval depends on the active sub-range: ≤1 inch WC: every 3 months; ≤2 inch WC: every 6 months; >2 inch WC: every 12 months. Procedure: power the sensor for at least 15 minutes, release both tube connectors from the + and - pressure ports (calibration is required even if display reads 0), press and hold the calibration button until the LED illuminates steadily, then wait for the LED to flash and reinstall the tubes (observing + and - polarity). Note: this SKU also has the auto-zero feature that handles routine zero-point correction automatically - manual calibration is needed less frequently as a result.
Key Features
Internal solenoid valve periodically isolates the sensor from the pressure ports and re-zeros the reading automatically - eliminates routine manual calibration drift, especially valuable at the most sensitive sub-ranges where a small offset translates to a large percentage error.
One SKU covers eight pressure ranges within the -0.4 to 10 inch WC envelope, selectable via on-board DIP switch. Narrower sub-ranges give higher analog resolution - particularly valuable for low-velocity filter monitoring and cleanroom applications.
Belimo's proven piezo measuring element with ±0.02 inch WC accuracy below 2 inch WC and ±0.04 inch WC above. Long-term stability ±2.5% FSO over 4 years. Covers low-velocity duct measurements where a thermal-mass element would be too noisy.
Burst pressure tolerance of 160 inch WC (40 kPa) - survives transient overpressure events from damper closures, fan starts, and pressure tests without damage.
Channel 2 outputs volumetric flow calculated from differential pressure and a configured K-factor. Selectable units: m³/h, m³/s, or cfm. Default range 0-750,000 cfm. Eliminates the need for a separate flow meter when the application has a known venturi or orifice K-factor.
UV-resistant orange polycarbonate housing rated NEMA 4X / IP65 (UL Enclosure Type 4X). UL 2043 plenum compliant for return-air ducts. UL94 5VA flame class. NBR70 seal for chemical resistance against typical HVAC environment exposures.
Industry-leading factory warranty backed by Belimo's worldwide service network.
Selectable Measuring Sub-Ranges (DIP Switch S0-S7)
The active measuring sub-range is set via on-board DIP switch (settings S0 through S7). The factory default is S0 (full range); narrow the range to higher S-numbers for low-velocity applications where higher analog resolution matters.
| Setting | inch WC | Pa | Note |
|---|---|---|---|
| S0 | 0-10 inch WC | 0-2500 Pa | ‚òÖ Factory setting |
| S1 | 0-8 inch WC | 0-2000 Pa | |
| S2 | 0-6 inch WC | 0-1500 Pa | |
| S3 | 0-4 inch WC | 0-1000 Pa | |
| S4 | 0-2 inch WC | 0-500 Pa | |
| S5 | 0-1 inch WC | 0-250 Pa | |
| S6 | 0-0.4 inch WC | 0-100 Pa | |
| S7 | -0.4-0.4 inch WC | -100-100 Pa | Bidirectional, most sensitive |
Technical Specifications
| Specification | Detail |
|---|---|
| Sensor Style | Active differential pressure transducer for air |
| Measured Values | Differential pressure, Volumetric flow |
| Measuring Fluid | Air and other non-aggressive, non-flammable gases |
| Sensing Element | Piezo measuring element |
| Output Signals | 2x active analog: Output 1 = Pressure, Output 2 = Volumetric Flow; 0-5V, 0-10V, or 4-20 mA switch-selectable |
| Output Load | min. 10 kΩ load resistance; mA output: max. 500 Ω loop resistance |
| Pressure Measuring Range (Default) | -0.4 to 10 inch WC (-100 to 2500 Pa) - DIP setting S0 |
| Pressure Measuring Range (Selectable) | 8 sub-ranges via DIP switch S0-S7 within the medium pressure envelope |
| Pressure Direction | Bidirectional |
| Pressure Accuracy | ≤2 inch WC: ±0.02 inch WC; >2 inch WC: ±0.04 inch WC |
| Long-Term Stability | ±2.5% FSO (Full Scale Output) per 4 years |
| Burst Pressure | 160 inch WC (40 kPa) |
| Volumetric Flow Range | Default 0-750,000 cfm; configurable |
| Volumetric Flow Units | m³/h, m³/s, or cfm (parameterizable) |
| Typical Response Time | Adjustable: 0.8 s or 4.0 s |
| Manual Zero-Point Calibration | Single-button with LED feedback; recommended every 3-12 months depending on range |
| Auto-Zero Feature | Yes - internal solenoid valve periodically re-zeros at configurable interval |
| Application | Air monitoring - duct-mounted |
| Mounting | Wall/duct mount with included A-22D-A10 mounting plate |
| Pressure Connection | Two ports (+/-) with included A-22AP-A08 duct connector kit (PVC tube + connectors) |
| Conduit | 1/2" NPT conduit adapter included; cable gland 2x Ø6 mm with strain relief |
| Power Supply | 24 VAC/VDC (19-29 VAC, 15-35 VDC) |
| Power Consumption | 4.3 VA AC / 2.3 W DC |
| Electrical Connection | Pluggable spring-loaded terminal block, max 2.5 mm² |
| Display | No display on this variant |
| Housing Material | Polycarbonate, orange - UL94 5VA, UV-resistant; NBR70 seal |
| Enclosure Rating | NEMA 4X / IP65, UL Enclosure Type 4X |
| UL 2043 Plenum Compliance | Suitable for use in air plenums per NEC 300.22(C) and IMC Section 602 |
| Protection Class | IEC/EN III, SELV (Safety Extra-Low Voltage) |
| Power Source UL | Class 2 Supply |
| Pollution Degree | 3 |
| Ambient Humidity | Max. 95% RH, non-condensing |
| Ambient Temperature | 14-122°F (-10 to 50°C) |
| Fluid Temperature | 15-120°F (-10 to 50°C) |
| Storage Temperature | -4 to 176°F (-20 to 80°C) |
| EU Conformity | CE Marking |
| Certification | IEC/EN 60730-1 and IEC/EN 60730-2-6 |
| Quality Standard | ISO 9001 |
| Manufacturer | Belimo |
| Manufacturer Part Number | 22ADP-584A |
| Warranty | 5-year factory warranty |
What's In the Box
- 22ADP-584A differential pressure transducer with auto-zero feature in orange polycarbonate housing
- A-22D-A10 mounting plate (L housing)
- A-22AP-A08 duct connector kit - 2 m PVC tube, 2x plastic duct connectors
- Cable gland with strain relief, Ø6...8 mm
- 1/2" NPT conduit adapter, 2x Ø6 mm
- Mounting dowels and screws
Compatible accessories sold separately: A-22AP-A01 metal duct connector (1.5" L, 0.2" tube connection) for steel ducts where the included plastic connectors are not preferred.
Documentation
Frequently Asked Questions
What does the 22ADP-584A measure and output?
It measures differential air pressure (between the + and - ports) and outputs volumetric flow calculated from that pressure plus a configured K-factor. Two analog outputs: AO1 = pressure, AO2 = flow, both switch-selectable between 0-5V, 0-10V, and 4-20 mA. Analog-only variant - no bus communication.
Why 8 measuring ranges? Which to use?
The 8 sub-ranges (S0-S7) let one sensor body cover applications across the -0.4 to 10 inch WC envelope. Choose the narrowest range that covers your expected reading - narrower ranges give higher analog resolution. Set via DIP switch.
Why use 4-20 mA instead of 0-10V?
4-20 mA current loops are immune to voltage drop on long cable runs (>~150 ft). The loop also has built-in fault detection: 0 mA = broken loop, vs 0V on a voltage output which could mean either zero reading OR broken wiring.
How does the Auto-Zero feature work?
An internal solenoid valve briefly isolates the sensor from the pressure ports at a configurable interval, reads its own zero reference, and updates the offset correction. Eliminates the drift that affects piezo sensors at low ranges - especially important for cleanroom/lab applications where a 0.05 inch WC offset would be a 5-50% reading error. Belimo still recommends annual manual zero-point verification.
How is volumetric flow calculated?
Volumetric flow Q = K x √(ΔP), where K is a K-factor specific to your venturi, orifice plate, or pitot tube. K-factor is set via Belimo Assistant 2 / dongle. Default 0-750,000 cfm full scale. Without a known K-factor, use only AO1 (pressure).
What is the burst pressure rating?
160 inch WC (40 kPa). Survives transient overpressure events (fan starts, damper closures, pressure tests) without calibration drift or seal damage.
How often is manual calibration needed?
Interval depends on active sub-range: 3 months at S5-S7 (≤1 inch WC), 6 months at S3/S4 (≤2 inch WC), 12 months at S0-S2 (>2 inch WC). Lower ranges drift more noticeably. Auto-Zero on this variant handles routine correction automatically.
How is this different from other 22ADP variants?
All 22ADP variants share the same chassis and piezo element. This SKU is the medium-range variant (-0.4 to 10 inch WC). Other ranges: 22ADP-556 (high, 0 to 28 inch WC); 22ADP-55Q (low, -0.6 to 1 inch WC). Output styles: -58x = V+mA analog only, -55x = V + Modbus RTU, -56x = V + BACnet MS/TP. Choose by BAS protocol and range.
Where can I install this sensor?
Wall or duct mount indoors, NEMA 4X / IP65. UL 2043 plenum compliant for return-air ducts (NEC 300.22(C)). Operating: 14-122°F ambient, 15-120°F fluid. Mounting plate and duct connector kit (2 m PVC tubing) included.
Power requirements?
24 VAC or 24 VDC (19-29 VAC, 15-35 VDC). Power consumption 4.3 VA AC / 2.3 W DC - compatible with standard 24V control transformers shared with actuators.
- Series:
- 22ADP
- Pressure Range:
- -0.4 to 10 inch WC (-100 to 2500 Pa)
- Range Class:
- Medium
- Direction:
- Bidirectional
- Output Signal:
- 0-5V / 0-10V / 4-20 mA
- Accuracy:
- +/-0.02 inch WC (<=2 in WC range), +/-0.04 inch WC (>2 in WC)
- Display:
- No
- NIST Certificate:
- None
- Mounting:
- Duct/Wall (Indoor)
- Made in USA:
- No
