Honeywell ST700 STD720-E1AS4AS-1-A-EHC-13C-B-61A6-FX Differential Pressure Transmitter

The Honeywell STD720-E1AS4AS-1-A-EHC-13C-B-61A6-FX F1 FE TP-0000 is a SmartLine ST700 differential pressure transmitter that is very accurate and works best for monitoring and controlling industrial processes. With a span accuracy of 0.05% and a strong build, it works great for monitoring flow, level, and filters in both marine and factory settings.

This Honeywell STD720 type is part of the ST700 series. It measures differential pressure with a range of -400 to 400 inH2O. It has a 316L SS diaphragm and DC 200 silicone fill fluid for consistent performance. With HART communication, built-in electronics, and advanced diagnostics, it can work in tough settings while still meeting SIL 2/3 safety standards. Because it has a modular architecture and a 100:1 turndown ratio, it can be used in HVAC, chemical processing, and maritime systems that need very accurate DP measurement.

Technical Specifications: Honeywell STD720

• Model and Range: STD720 differential pressure transmitter, -400 to 400 inH2O (-1000 to 1000 mbar)

• Accuracy: 0.05% of span standard (up to 0.04% optional), 0.0375% static pressure accuracy

• Process Connections: 1/4″ NPT female on 316 SS heads, glass-filled PTFE gaskets

• Fill Fluid/Diaphragm: DC 200 silicone, 316L SST diaphragm

• Output Signal: 4-20 mA with HART 7 protocol, 10.8-42.4 VDC supply

• Temperature Limits: Ambient -40°C to 85°C, storage -55°C to 120°C​

• Housing: Low-copper aluminum, polyester-coated (NEMA 4X/IP66/67), optional SS​

• Certifications: FM, CSA, ATEX, IECEx, SIL 2/3, MAWP 4500 psi

• Stability: 0.02% URL per year for 10 years, 100 ms response time

• Weight: Approx. 7-10 lbs depending on configuration

Honeywell STD720 Key Features:

1) Built-in static pressure compensation gives you better flow and level measurements with an accuracy of 0.05% and a turn down of 100:1.

2) The modular LCD display may be turned 0 to 270 degrees and has two or three buttons for easy configuration on site without equipment.

3) Full diagnostics, including fault alarms and SIL-compliant safety, for less maintenance in industrial settings.

4) This tough coplanar platform can handle up to 4500 psi of overpressure, making it perfect for marine and industrial settings

5) HART-enabled for remote monitoring and works with DCS/PLC systems like Experion PKS.

Honeywell ST 700 Datasheet

Download datasheet file

How to Use?

• Use a bracket or flange to mount it either vertically or horizontally. For spans under 10 inH2O, use a spirit level to make sure it’s level.
• Use a 3-valve manifold to connect high- and low-pressure lines to 1/4″ NPT ports. Before starting, exhaust or purge air from the impulse lines.
• Connect the 4-20 mA loop to terminals that don’t care about polarity (16 AWG max), give it 10.8–42.4 VDC power, and check the output signal.
• Use buttons or a HART communicator to make zero and span adjustments while the process is isolated. Set up units, damping, and alerts on the display.
• Use the MC Toolkit or HART device to calibrate once a year and keep an eye on diagnostics for problems like overpressure or sensor drift.