Honeywell STR735D Remote Diaphragm Seal Transmitter

Model：STR735D-21CS1D0-JKGJDCD0T-C-BHT-11S-B-31A7-FX,F1-0000

Manufacturer: Honeywell

Size: 50*50*25CM

Detail Specification: Differential Pressure Transmitter

Comment:Carton

Shipping Weight: 30Kg

Estimated Lead Time: 12 Weeks

Payment：T/T

HS CODE：9026201090

product details

Honeywell STR735D Remote Diaphragm Seal Transmitter

Product Overview

Honeywell STR735D Remote Diaphragm Seal Transmitter belongs to the SmartLine® ST700 family, a series of high-performance pressure transmitters hydraulically matched and optimized with a complete set of remote diaphragm seals-1. The STR735D utilizes Honeywell‘s advanced SmartLine sensor technology, integrating piezoresistive pressure sensing with on-chip static pressure and temperature compensation capabilities-1. This design significantly reduces the temperature effects that commonly plague remote flange measurements, delivering high accuracy, stability, and reliable performance across a broad range of process pressures and temperatures-1.

The STR735D SmartLine Pressure Transmitter with Remote Diaphragm Seals transmits process pressure through fill fluid within remote flanges and capillaries, isolating the transmitter electronics from harsh process conditions while maintaining measurement integrity-1. Honeywell offers the STR735D with multiple seal configurations including flush flange seals, flange seals with extended diaphragm, pancake seals, sanitary seals, chemical tee Taylor wedge, saddle seals, threaded process connection seals, calibration rings, stainless steel armored capillaries, PVC-coated stainless steel armored capillaries, 2-inch stainless steel nipples, and welded meter bodies-1.

Key Takeaway: Honeywell STR735D Remote Diaphragm Seal Transmitter is the ideal choice when process media are corrosive, viscous, prone to crystallization, or operate at extreme temperatures that would damage a standard pressure transmitter.

Key Features of Honeywell STR735D SmartLine® Pressure Transmitter

The STR735D SmartLine Pressure Transmitter with Remote Diaphragm Seals delivers a comprehensive suite of performance-enhancing features:

Feature Category	Details
Sensor Technology	Piezoresistive sensor with on-chip static pressure and temperature compensation
Turndown Ratio	Up to 111:1 (industry-leading rangeability)
Accuracy	Up to 0.075% of calibrated span (standard)
Stability	0.015% of URL per year (typical), maintaining 5+ years
Response Time	As fast as 100 ms
Output Signal	4-20 mA with HART v7.0 communication protocol
Supply Voltage	10.8 to 42.4 VDC (IS versions limited to 30 VDC)
Load Resistance	0 to 1,440 ohms
Configuration	External zero, span, and configuration capability; three-button local configuration
Diagnostics	Comprehensive on-board diagnostics; SIL 2/3 certified
Safety Design	Integral dual seal design per ANSI/NFPA 70-202 and ANSI/ISA 12.27.0
Housing Protection	IP66 / IP67 (depending on configuration)
Display Option	Modular alphanumeric LCD (field-addable/removable, 0°/90°/180°/270° rotatable)
Polarity	Polarity insensitive electrical connections
Approvals	FM, CSA, ATEX, IECEx, NEPSI, KOSHA, EAC, CCoE, UATR, SAEx, INMETRO

The STR735D SmartLine Pressure Transmitter’s 111:1 turndown ratio allows a single transmitter to cover multiple pressure ranges, reducing inventory requirements and simplifying engineering specifications-1. The comprehensive on-board diagnostics help maintain high uptime, meet regulatory requirements, and achieve stringent quality standards-1.

Technical Insight: The STR735D Remote Diaphragm Seal Transmitter achieves its high performance through a single piezoresistive sensor that integrates multiple sensing elements—process pressure measurement, static pressure (for DP models), and temperature compensation—all on one chip.

Detailed Technical Specifications

The following technical parameters define the performance envelope of the Honeywell STR735D Remote Diaphragm Seal Transmitter:

Pressure Ranges and Span Limits

Parameter	Specification
Model	STR735D SmartLine Pressure Transmitter with Remote Diaphragm Seals
Maximum Working Pressure Range	-100 to +100 psig (-7 to 7 bar)
Minimum Span	0.9 psid (0.062 bar)
Maximum Span	100 psid (7 bar)
Maximum Allowable Working Pressure (MAWP)	750 psig (51.7 bar)
Measurement Type	Differential Pressure (DP) with Remote Diaphragm Seals
Overpressure Protection	World-class, dual-seal design

Accuracy and Performance

Parameter	Specification
Reference Accuracy	Up to ±0.075% of calibrated span
Accuracy (Optional)	0.065% span (available on select configurations)
Stability	0.02% of URL for 10 years (typical)
Turndown Ratio	111:1
Ambient Temperature Limits (Operation)	-20 to +70°C (with LCD display)
Ambient Temperature Limits (Storage)	-55 to +90°C
Relative Humidity	0 to 100% RH
Supply Voltage Effect	0.005% of span per volt

The STR735D‘s accuracy specification applies across the full turndown range, meaning a STR735D SmartLine Pressure Transmitter calibrated at 100 psid and turned down to measure 0.9 psid maintains the same ±0.075% accuracy—a critical advantage for applications requiring wide rangeability.

Electrical and Communication Specifications

Parameter	Specification
Output Signal	4-20 mA DC, HART v7.0 (digital protocol)
Supply Voltage Range	10.8 to 42.4 VDC
Load Resistance	0 to 1,440 ohms at 24 VDC
Response Time (programmable)	0 to 60 seconds
Minimum Response Time	100 ms
Communication Protocols	HART v7.0 (standard), Honeywell DE (optional), Foundation Fieldbus (optional)

Compatibility Note: The STR735D Remote Diaphragm Seal Transmitter with HART v7.0 protocol is fully backward compatible with HART v5.x and v6.x host systems, ensuring seamless integration into existing control infrastructures.

Physical Specifications and Materials of Construction

Component	Specification
Wetted Materials	316L Stainless Steel (standard); Hastelloy C-276, Monel, Tantalum (optional)
Non-Wetted Materials	316L Stainless Steel, 316 SS, Carbon Steel (depending on configuration)
Fill Fluid (Standard)	Silicone Oil 200 (DC 200)
Alternative Fill Fluids	Fluorolube, Neobee, Glycerin/Water, High-temperature fill fluids
Housing Material	Aluminum with polyester coating (standard) or 316 Stainless Steel (CF8M grade)
Electrical Connection	1/2 NPT female conduit entry
Process Connections	Flush flanged seals, extended diaphragm flange seals, threaded connections, pancake seals, sanitary seals
Diaphragm Diameter Options	3.5 inches (90mm), 4.1 inches (104mm), and other sizes available
Flange Pressure Ratings	ANSI 150, ANSI 300, DIN PN40, and others
Capillary Length	Customizable from 5 ft to 50 ft (1.5m to 15m) standard; longer lengths available
Capillary Armor	Stainless steel armor (standard); PVC-coated stainless steel armor (optional)

The STR735D SmartLine Pressure Transmitter’s modular design allows field replacement of electronic modules, display units, and terminal blocks without de-pressurizing the process—significantly reducing maintenance downtime.

Remote Seal Configurations

The STR735D Remote Diaphragm Seal Transmitter supports an extensive range of remote seal types to match virtually any process connection requirement-1:

Seal Type	Typical Application
Flush Flange Seals	Standard applications with flanged connections
Extended Diaphragm Flange Seals	Viscous or solids-laden fluids requiring diaphragm extension into process flow
Pancake Seals	Space-constrained installations
Sanitary Seals	Food, beverage, and pharmaceutical (3A sanitary compliant)
Chemical Tee Taylor Wedge	Chemical processing with corrosion-resistant requirements
Threaded Connection Seals	Small-bore piping and high-pressure applications
Saddle Seals	Tank and vessel side-mount installations
Calibration Rings	In-situ verification and calibration access

Each seal configuration includes a specific ordering code. For example, STR735D-21CS1E0-AFCAA21BS-A-EHS-11S-A-11A0 designates a dual-seal configuration with 316 SS bolt-on heads, 25 ft (7.5m) stainless steel armored capillary, and flush flanged seal with 3.5-inch diaphragm and 3-inch ANSI 300 flange rating-2. The ordering code structure follows Honeywell‘s modular selection guide, enabling precise specification of fill fluids, wetted materials, capillary lengths, and seal dimensions.

Industry Applications

The STR735D SmartLine Pressure Transmitter with Remote Diaphragm Seals excels in demanding process environments where direct instrument contact with process media is undesirable or impossible. Primary application areas include-18:

Oil and Gas / Hydrocarbon Processing

High-accuracy level measurement in pressurized vessels

Refinery column level monitoring

Pipeline differential pressure measurement

Separator and treater level control

Crude oil tank level with interface detection

Chemical Processing

Flow measurement of slurries and high-viscosity process fluids

Corrosive chemical storage tank level

Reactor pressure and level monitoring

Crystallizer and evaporator pressure control

Acid and caustic service with corrosion-resistant wetted materials

Power Generation

Boiler drum level measurement

Condenser level monitoring

Feedwater heater level control

Steam pressure measurement with remote seals for high-temperature isolation

Pulp and Paper

Digester pressure and level

Black liquor tank measurement

Paper machine stock approach systems

Chemical recovery boiler monitoring

Pharmaceutical and Biotechnology

Sanitary tank level measurement (3A compliant configurations)

Fermenter and bioreactor pressure monitoring

Purified water and WFI storage tank level

Solvent recovery systems

Food and Beverage

Sanitary process vessels

Cooking and mixing tanks

Storage silo level

CIP/SIP system pressure monitoring

Water and Wastewater Treatment

Sludge level measurement

Chemical storage tank level (coagulants, flocculants, polymers)

Pump suction pressure monitoring

Digester level control

Application Example: In a chemical plant handling hydrochloric acid at 150°C, the STR735D Remote Diaphragm Seal Transmitter with Tantalum wetted diaphragm and high-temperature fill fluid isolates the electronics from both corrosive attack and thermal degradation while delivering ±0.075% level measurement accuracy.

The STR735D is also well-suited for high-temperature process fluids (up to 338°C / 640°F depending on seal and fill fluid selection), high-vacuum distillation column level measurement, viscous and crystallizing liquids, sanitary applications requiring 3A compliance, and tank applications requiring density or interface measurement-1.

Installation and Configuration

The STR735D SmartLine Pressure Transmitter simplifies field installation and commissioning through several user-centric design features:

External Zero, Span, and Configuration: Three externally accessible buttons allow field adjustment of zero, span, and basic configuration parameters without removing the housing cover—no special tools or handheld communicator required for routine adjustments-1.

Polarity Insensitive Wiring: Electrical connections tolerate reversed polarity, preventing wiring errors from damaging the transmitter and reducing commissioning time.

Modular Display: The alphanumeric LCD display module can be added or removed in the field and rotated in 90° increments to accommodate any mounting orientation-1.

Multi-Unit Display: The STR735D Remote Diaphragm Seal Transmitter supports display in engineering units including Pa, kPa, MPa, kg/cm², Torr, atm, inH₂O, mH₂O, bar, mbar, inHg, ftH₂O, mmH₂O, mmHg, and psi.

HART v7.0 Communication: Full device description (DD) and DTM support for configuration, monitoring, diagnostics, and maintenance through any HART-compliant host system-1.

Installation best practices for the STR735D SmartLine Pressure Transmitter include:

Mount transmitter at or below the lower process connection for liquid applications

Ensure vertical capillary runs are properly supported to prevent sagging

Maintain minimum bend radius of 6 inches (152 mm) on armored capillaries

Verify fill fluid compatibility with process temperature extremes

Perform zero trim after installation with equalized pressure across both seals

Certifications and Compliance

The STR735D Remote Diaphragm Seal Transmitter carries a comprehensive suite of global certifications:

Certification	Standard
Functional Safety	IEC 61508 SIL 2/3 certified (full compliance as standard)
Explosion Protection	FM, CSA, ATEX, IECEx, NEPSI, KOSHA, EAC, CCoE, UATR, SAEx, INMETRO
Dual Seal Design	ANSI/NFPA 70-202 and ANSI/ISA 12.27.0
NAMUR Compliance	NE-43 (fault signal levels)
Marine Approvals	Available upon request
Sanitary Compliance	3A (with appropriate seal configuration)

All STR735D SmartLine Pressure Transmitters are fully tested for Experion PKS compatibility, providing the highest level of integration assurance and performance optimization within Honeywell control systems-1.

Ordering Information

Honeywell STR735D Remote Diaphragm Seal Transmitters follow a modular ordering code system. Complete part numbers include selections for:

Seal type and quantity (1 or 2 remote seals)

Primary fill fluid (meter body)

Secondary fill fluid (capillary and seals)

Capillary length and armor type

Seal diaphragm diameter and flange rating

Wetted and non-wetted materials

Flushing connections and plugs

Approvals and certifications

Housing material and electrical connection type

Output protocol (4-20mA HART / DE / Foundation Fieldbus)

Display and configuration interface options

Accuracy grade and calibration requirements

Mounting bracket type and material

Customer tag and labeling

Example complete model numbers:

STR735D-21CS1E0-AFCAA21BS-A-EHS-11S-A-11A0

STR735D-21CC1CC0-DDABA400K-A-AHS-11C-A-11A0-F1

STR735D-21CC1E0-AFCAA21BS-A-BHS-11C-B-11A0-F1,F5

STR735D-21CS1E0-(YYY)AA21BS-A-EHS-11S-A-11A0 (Y=600)

Ordering Note: For applications requiring extended temperature ranges or special fill fluids, consult the Honeywell STR700 Technical Specification (document 34-ST-03-104) or contact your local Honeywell representative for assistance with non-standard configurations.

Why Choose Honeywell STR735D Over Competitors?

The STR735D SmartLine Pressure Transmitter with Remote Diaphragm Seals offers distinct advantages compared to alternative remote seal transmitters in the market:

Feature	Honeywell STR735D	Typical Competitor
Turndown Ratio	111:1	100:1 maximum
Standard Accuracy	0.075%	0.10% typical
External Config Buttons	Standard (3 buttons)	Often optional or absent
Polarity Protection	Standard	Not always standard
Dual Seal Certification	Standard (SIL 2/3)	Often optional at added cost
HART Version	v7.0 (backward compatible)	v5.x or v6.x typical
Temperature Compensation	On-chip static & temp	External or separate sensor

The STR735D‘s combination of 111:1 turndown, 0.075% standard accuracy, and comprehensive onboard diagnostics—all at a competitive price point—delivers exceptional value for applications requiring remote diaphragm seals-1. The integrated dual seal design provides ANSI/ISA 12.27.0 certification as standard, not as an add-on option-1.