The ACI P51-50-A-A-P-20MA-000-000 is a 304L stainless steel absolute pressure transducer from the ACI P51 Series, built for accurate, reliable measurement in commercial, industrial and process-control applications where performance is critical. The P51-50-A-A-P-20MA-000-000 is configured for a 50 PSI full-scale range and delivers a linear 4 to 20 mA (2-Wire, Loop Powered) output. It measures pressure relative to a perfect vacuum (0 PSIA), giving a reading that is independent of weather, altitude or temperature, with a factory-calibrated accuracy of < +/- 0.5% FS (including hysteresis, repeatability and non-linearity, BFSL).
At the core of the P51-50-A-A-P-20MA-000-000 is a bulk micro-machined transducer with a welded 304L stainless steel diaphragm that contains no O-rings, making the P51-50-A-A-P-20MA-000-000 compatible with virtually any gas or liquid that is compatible with 304L Stainless Steel — including refrigerants, glycol, motor oil, diesel, hydraulic fluid, brake fluid, water, waste water, hydrogen, nitrogen and air. The process connection is a 1/4"-18 NPT fitting in 304L Stainless Steel with a 7/8" Hex wrench flat, and the unit terminates in a Packard 3-pin connector; the mating cable harness (A/GP) is ordered separately. As a PSIA unit, the P51-50-A-A-P-20MA-000-000 references a perfect vacuum and is calibrated to read its zero output at 0 PSIA (-14.7 PSI gage).
Warranty
LIMITED
WARRANTY
Manufacturer-backed coverage. ACI P51 Series transducers carry a Two (2) Year Limited Warranty. ZOT Supply is an authorized ACI distributor; the P51-50-A-A-P-20MA-000-000 ships factory-new with full manufacturer warranty intact and access to ACI technical support. Full terms appear in the front of ACI’s Sensors & Transmitters catalog and at workaci.com.
Key Features
Bulk Micro-Machined Stainless Diaphragm
Solid-state stainless steel sensing element with welded construction and no O-rings. The P51-50-A-A-P-20MA-000-000 delivers stable, drift-resistant performance and broad media tolerance across a wide pressure and temperature range.
4 to 20 mA Output
The P51-50-A-A-P-20MA-000-000 provides a linear 4 to 20 mA (2-Wire, Loop Powered) signal proportional to the applied pressure. Loop-powered 2-wire installation that integrates directly with PLCs, BAS controllers, recorders, and data-acquisition systems.
< +/- 0.5% FS Accuracy
Total accuracy spec at 22°C (71.6°F) of < +/- 0.5% FS that includes hysteresis, linearity and repeatability (BFSL). Long-term stability of +/- 0.03% FS @ 0 PSIG.
1/4"-18 NPT Process Connection
The P51-50-A-A-P-20MA-000-000 connects through a 1/4"-18 NPT male fitting machined from 304L Stainless Steel, with a 7/8" Hex wrench flat. Recommended install torque is 150 lbs-in (16.95 Nm). Use thread sealant; do not use a strap wrench on the body.
Robust Overpressure & Environmental Margin
Proof pressure: 3X FS. Burst pressure: 10X FS or 15,000 PSI (whichever is less). Vibration tested 144 hours (100–2000 Hz, 20g sinusoidal, 3 axes). Operating range -40 to 257°F (-40 to 125°C). The P51-50-A-A-P-20MA-000-000 tolerates demanding service environments.
Recognized Approvals
The P51-50-A-A-P-20MA-000-000 is built to UKCA, CE, RoHS2, WEEE and ISO 9001 standards, with 150 V/m EMC immunity. Optional NIST calibration certificate (GP NIST) available as a separate line item.
Technical Specifications
| Specification | Value |
|---|---|
| Model | P51-50-A-A-P-20MA-000-000 |
| Pressure Sensing Type | Absolute Pressure (PSIA) |
| Full Scale Pressure Range | 50 PSI |
| Accuracy @ 22°C (71.6°F) | < +/- 0.5% FS (Hysteresis, Repeatability, Non-linearity BFSL) |
| Output Signal | 4 to 20 mA (2-Wire, Loop Powered) |
| Supply Voltage | 250 Ohm Load: +13 to 30 VDC | 500 Ohm Load: +18 to 30 VDC |
| Supply Current | 25 mA minimum |
| Output Load Impedance | 800 Ohms maximum @ 24 VDC | Formula: (Supply VDC - 8 VDC) / 0.020A |
| Reverse Polarity Protection | +/- 16 V over 5 minutes |
| Thermal Error (-40 to 105°C) | < +/- 0.5% FS |
| Stability (250 Hrs @ 225°F) | +/- 0.03% FS @ 0 PSIG; +/- 0.12% FS @ 1000 PSIG |
| Response Time | < 1 ms |
| Proof Pressure | 3X FS |
| Burst Pressure | 10X FS or 15,000 PSI (whichever is less) |
| Thermal Shock | 300 Cycles (105°C to -40°C, 0.5 hr soaks @ Temperature, 2s Transfer) |
| Vibration | 144 Hours (100 to 2000 Hz, 20g Sinusoidal, 3 Axes) |
| Operating Temperature | -40 to 257°F (-40 to 125°C) |
| Storage Temperature | -40 to 176°F (-40 to 80°C) |
| Operating Humidity | 0 to 95% RH, non-condensing |
| Media Type | Any gas or liquid compatible with 304L Stainless Steel |
| Housing Material | Stainless Steel |
| Process Fitting Material | Thread | 304L Stainless Steel | 1/4"-18 NPT |
| Wrench Flat | 7/8" Hex |
| Recommended Torque | 150 lbs-in (16.95 Nm) |
| Wiring Connection | A Packard 3-pin connector; the mating cable harness (A/GP) is ordered separately |
| Wiring | 2-Wire loop: Power (Red) to supply +, Return (White) to the controller current input, Shield (Green) to earth ground |
| NIST Calibration Certificate | Optional, ordered separately (GP NIST) |
| Approvals | UKCA, CE, RoHS2, WEEE, ISO 9001 |
| EMC Compatibility | 150 V/m |
| Product Dimensions (L x Dia) | 2.60" (66.6 mm) L x 0.875" (22.23 mm) Dia |
| Product Weight | 0.32 lbs (0.145 kg) |
| Minimum Order Quantity | 10 Units |
| Manufacturer Part Number | P51-50-A-A-P-20MA-000-000 |
Documentation
Frequently Asked Questions
What does the P51-50-A-A-P-20MA-000-000 measure?
The P51-50-A-A-P-20MA-000-000 is a absolute pressure transducer with a 50 PSI full-scale range. It measures pressure relative to a perfect vacuum (0 PSIA), giving a reading that is independent of weather, altitude or temperature. Proof pressure is 3X FS and burst pressure is 10X FS or 15,000 PSI (whichever is less), giving substantial overpressure margin.
What output does the P51-50-A-A-P-20MA-000-000 provide and how is it wired?
The P51-50-A-A-P-20MA-000-000 provides a 4 to 20 mA (2-Wire, Loop Powered) output. 2-Wire loop: Power (Red) to supply +, Return (White) to the controller current input, Shield (Green) to earth ground.
What media is the P51-50-A-A-P-20MA-000-000 compatible with?
The welded 304L stainless steel diaphragm of the P51-50-A-A-P-20MA-000-000 contains no O-rings, so it is compatible with any gas or liquid compatible with 304L Stainless Steel — refrigerants, glycol, oils, water, waste water, hydrogen, nitrogen and air. See the 304L Chemical Compatibility Chart linked in the Documentation section for a full list of compatible media.
Does the P51-50-A-A-P-20MA-000-000 need a pressure snubber?
ACI recommends a 1/4" stainless steel snubber (A/0.25" SNUB A/G for air and gas, or A/0.25" SNUB WTR for water and light oils) with the P51-50-A-A-P-20MA-000-000 to smooth out pressure spikes, surges and pulsations and to keep debris out of the sensor diaphragm. For steam service, an A/Syphon pigtail (90°, 180° or 270°) is also recommended.
Why is there a 10-piece minimum order quantity?
The P51-50-A-A-P-20MA-000-000 is a factory-direct ACI product configured to your selected pressure range, port, connector and output. ACI sets a minimum order quantity of ten (10) pieces on these built-to-order P51 SKUs. ZOT Supply passes this minimum through directly — orders below 10 units cannot be processed. If you need a different configuration, a different quantity, or have a project-specific question, contact ZOT Supply and we will work with you on the best path forward.
- Pressure Type:
- Single
- Pressure Sensing:
- Absolute
- Media:
- Wet
- Pressure Range:
- 50 PSI
- Output Signal:
- 4-20mA
- Process Connection:
- 1/4 inch NPT
- Wetted Material:
- 304L Stainless Steel
- Min Order Qty:
- 10 Units
