Description
1. Product Overview
Allen‑Bradley 1797‑PS2E2 is a high‑performance DC‑input intrinsically‑safe explosion‑proof power supply module of Rockwell Automation FLEX Ex series. Developed for high‑risk flammable and explosive conditions such as Zone 0, Zone 1, Zone 2 and Zone 22 in chemical, petrochemical, oil‑gas, pharmaceutical and dust‑explosion industries, it serves as the core power‑supply unit for FLEX Ex explosion‑proof distributed I/O systems. Different from the AC‑input model PS1E, this module adopts a DC‑redundant power‑supply architecture with fault‑tolerant dual‑channel DC input. It provides four‑channel independent isolated intrinsically‑safe power for field intrinsically‑safe explosion‑proof I/O modules, explosion‑proof sensors and field measuring instruments, eliminating explosion hazards caused by electric sparks, high temperature and overload at the electrical fundamental level.
Featuring redundant input fault tolerance, independent intrinsically‑safe current‑voltage limiting for four channels, full electrical isolation and fault latching protection, the module operates reliably under severe industrial explosion‑proof conditions and supports 7×24‑hour non‑stop continuous operation. Thanks to redundant power supply, high stability and strong fault tolerance, it is widely adopted for new assembly of high‑risk explosion‑proof automatic‑control systems, replacement of legacy explosion‑proof power supplies and compliance retrofitting of explosion‑proof systems. It is the premium standard redundant power supply for FLEX Ex explosion‑proof I/O systems.
2. Functional Features
Dual‑channel DC redundant input for higher power‑supply fault‑tolerance Equipped with two independent DC power‑supply input ports for parallel redundant power supply. Power‑off, voltage drop or fault on one input channel will not affect normal output of the module, eliminating shutdown risks induced by single‑point failure of single‑source power supply. Suited for unattended high‑risk explosion‑proof sites, it greatly improves power‑supply continuity and operational reliability of explosion‑proof automation systems, and meets non‑stop production requirements of critical petrochemical and oil‑gas processes.
Four‑channel independent intrinsically‑safe isolated output for zoned safe power supply Four fully independent intrinsically‑safe output channels with complete electrical isolation between channels as well as between input and output to avoid mutual crosstalk. Each channel can independently power intrinsically‑safe I/O modules, explosion‑proof temperature/pressure/level sensors and discrete explosion‑proof instruments. Short‑circuit, overload or fault on a single channel triggers latching and isolation without impacting other channels or the whole substation, substantially enhancing system fault tolerance and operational‑maintenance safety.
Hardware‑based intrinsically‑safe parameter clamping for intrinsic‑safety explosion protection Precise voltage, current and power limiting implemented by hardware circuits. Maximum output power per channel reaches 8.5 W and total module output power is 34 W. Under normal operation as well as fault conditions including short‑circuit, overload and abnormal temperature rise, energy released at output terminals is always lower than the ignition energy of flammable‑explosive media. No electric spark or abnormal high temperature occurs. It fully complies with intrinsic‑safety specifications for gas and dust explosion‑hazardous areas with excellent compliance performance.
Full‑isolation anti‑interference design for complex electromagnetic environments Complete electrical isolation between input‑output and among channels. Built‑in filter and surge‑suppression circuits effectively reject industrial‑grid noise, harmonic distortion from frequency converters and high‑frequency electromagnetic crosstalk. It protects downstream precision explosion‑proof instruments and I/O modules from interference damage and prevents field faults from striking back to core cabinet equipment, applicable to chemical explosion‑proof workshops with intensive strong‑interference devices.
Multi‑functional intelligent latching protection for safe and controllable fault handling Integrated comprehensive protection of overvoltage, overcurrent, short‑circuit and overtemperature. Upon abnormality on any channel, power of the faulty loop is cut off instantly with fault state latched to prevent fault propagation and explosion accidents. Operation personnel can restore running by manual reset after hazard elimination. Clear fault indication and reliable actuation guarantee safe controllable operation for unattended high‑risk explosion‑proof sites.
- High‑grade explosion‑proof protection for long‑term service under wide‑temperature conditions High‑strength Ex d flame‑proof alloy housing certified by multiple international explosion‑proof standards, suitable for full‑range high‑risk explosion‑proof areas including Zone 1, Zone 2 and Zone 22. With outstanding protection performance against dust, splash water, moisture, corrosion, vibration and shock, it runs stably across wide temperature range and withstands harsh field conditions of petrochemical and oil‑gas sites such as high/low temperature, humidity and corrosion, delivering long maintenance‑free service life.
3. Technical Specifications
3.1 Basic Specifications
Product Model: 1797‑PS2E2 Manufacturer: Allen‑Bradley (Rockwell Automation) Product Series: 1797 FLEX Ex Explosion‑Proof Distributed I/O System Product Type: Flame‑proof and intrinsically‑safe redundant DC explosion‑proof power‑supply module Core Positioning: Redundant safety power‑supply unit for high‑risk explosion‑proof I/O substations, intrinsically‑safe instruments and explosion‑proof sensors Key Characteristics: Dual‑channel DC redundant input, four‑channel independent intrinsically‑safe output, full electrical isolation, multi‑fault latching protection, wide‑temperature operation, international explosion‑proof certifications, 7×24‑hour continuous operation.
3.2 Input Electrical Parameters
Input Mode: Dual‑channel redundant independent DC input Input Voltage Range: 18～32 V DC (nominal 24 V DC industrial standard) Input Features: Built‑in reverse‑connection protection, surge‑resistance and filter protection; supports hot‑standby fault‑tolerant dual‑power operation; single‑channel power loss does not affect module performance.
3.3 Intrinsically‑Safe Output Parameters
Output Channels: 4 independent intrinsically‑safe isolated channels Single‑channel Maximum Output Power: 8.5 W Total Module Output Power: 34 W Output Characteristics: Hardware‑implemented constant‑voltage and constant‑current intrinsic‑safety limitation Channel Isolation: Full electrical isolation between channels and between input and output Protection Mechanism: Independent latching protection for short‑circuit, overload, overvoltage and overtemperature on each channel; faulty channel isolated individually.
3.4 Mechanical and Wiring Parameters
Explosion‑proof Wiring Ports: Standard M16×1.5 explosion‑proof cable glands Applicable Cable Diameter: 4～8 mm industrial special explosion‑proof cables Mounting Method: Wall‑mount inside explosion‑proof enclosures, embedded mounting in explosion‑proof cabinets Housing Material: High‑strength explosion‑proof flame‑retardant alloy housing, shock‑resistant, corrosion‑resistant, insulating and flame‑retardant.
3.5 Environmental Operating Parameters
Operating Temperature: ‑40℃～+70℃ ultra‑wide temperature range Storage Temperature: ‑25℃～+80℃ Relative Humidity: 5%～95% non‑condensing Environmental Resistance: Tolerant of sharp temperature‑humidity variation, industrial vibration, mild corrosion, dust and oil accumulation Operation Mode: 7×24‑hour non‑stop continuous operation all‑year‑round Applicable Conditions: High‑risk severe scenarios such as petrochemical, oil‑gas, fine‑chemical, pharmaceutical and dust‑explosion industries.
4. Hardware Configuration & Structural Advantages
Dual‑channel DC redundant input eliminating power‑supply single‑point failure Compared with conventional single‑input explosion‑proof power supplies, 1797‑PS2E2 adopts dual‑DC redundant power‑supply architecture with two power sources in hot‑standby mode. Seamless output sustainment occurs when one source suffers abnormality, power‑off or voltage drop, ensuring non‑stop running of critical explosion‑proof processes. It significantly improves safety continuity of high‑risk production systems and represents the preferred power‑supply scheme for critical explosion‑proof loops.
Four‑channel independent isolated intrinsically‑safe output with superior zoned‑power‑supply safety Four channels are fully electrically isolated with independent intrinsic‑safety protection. Sensors and I/O modules at different process points can be powered separately without mutual interference. Automatic latching‑isolation upon single‑channel fault avoids total substation power loss. Troubleshooting on one channel can be performed without interrupting other process points, delivering better system fault tolerance and maintainability than conventional centralized power supplies.
Hardware‑based intrinsic‑safety clamping for intrinsic safety under all operating conditions Triple rigid limitation of voltage, current and power realized by pure hardware circuits. Output energy stays below explosion threshold under normal and fault conditions including line short‑circuit and overload, fundamentally removing electric‑ignition risks. It meets domestic and international explosion‑proof acceptance codes and fits highest‑grade intrinsic‑safety explosion‑proof applications with outstanding compliance, safety and reliability.
Full‑isolation anti‑interference architecture for extremely stable system operation Full electrical isolation between input‑output and among channels suppresses grid surges, harmonic interference and electromagnetic crosstalk. It guarantees stable signal acquisition of downstream precision explosion‑proof instruments against signal drift and jitter, and blocks field faults from breaking through cabinet equipment. Suitable for workshops densely equipped with frequency converters and high‑frequency devices under heavy electromagnetic interference.
Wide‑temperature industrial adaptability for versatile severe‑condition deployment Stable operation from ‑40℃ to +70℃ enables deployment in extremely cold outdoor sites, high‑temperature workshops and closed explosion‑proof enclosures with drastic temperature variation. It solves common problems of ordinary power supplies such as shutdown, unstable voltage and false protection under high/low temperature, and adapts to complex conditions at high‑risk sites all‑weather.
- Integrated modular design for convenient maintenance and replacement Integrated monolithic explosion‑proof structure without complex external accessories, featuring simple installation and standardized wiring. Faulty modules can be inspected, reset or replaced independently without modifying the whole explosion‑proof power‑supply loop and cabling. It greatly reduces maintenance difficulty and equipment downtime at high‑risk explosion‑proof sites, satisfying requirements of continuous‑safe production.
5. Application Scenarios
Critical explosion‑proof process systems for petrochemical and chemical industries: Deployed in high‑risk explosion‑proof workshops of refining, fine‑chemical and coal‑chemical plants. It supplies redundant safety power for FLEX Ex explosion‑proof I/O substations and intrinsically‑safe temperature/pressure/level/flow sensors of critical processes to guarantee non‑stop operation of continuous explosion‑proof production processes.
Explosion‑proof applications for oil‑gas production, storage and transportation: Applied in high‑risk Zone 1/Zone 2/Zone 22 areas of oilfields, gas fields, long‑distance oil‑gas pipelines and storage depots. It delivers fault‑tolerant redundant power for field remote explosion‑proof I/O substations and measuring instruments, solving problems of unstable field power and shutdown caused by single‑point failure.
Dust‑explosion‑proof systems for pharmaceutical and light‑industry sectors: Used in scenarios with flammable dust or vapour including pharmaceutical‑chemical processing, food powder production and building‑material powder manufacturing. Matched with explosion‑proof automation equipment to satisfy standards of safety production, explosion‑proof acceptance and compliance‑oriented technical retrofitting.
- High‑end complete projects with explosion‑proof redundant power supply: Serving as core redundant fault‑tolerant power‑supply accessory for critical automation systems where process shutdown is forbidden, so as to raise safety level and operational stability of overall explosion‑proof systems.
6. Product Advantages
Dual‑channel DC redundant power supply free of single‑point failure: Hot‑standby fault‑tolerant dual‑power architecture eliminates shutdown risks from single‑source power supply, suited for scenarios requiring non‑stop critical‑process production.
Four‑channel independent intrinsically‑safe channels with strong safety and fault tolerance: Independent isolation and protection per channel; single‑channel fault will not cause whole‑station failure. Zoned power supply achieves higher safety and easier maintenance.
Hardware‑enabled intrinsic safety with full‑mark explosion‑proof compliance: Triple rigid clamping of electrical parameters eliminates explosion‑ignition hazards under all operating conditions and meets highest‑grade domestic and international intrinsic‑safety codes.
Stable wide‑temperature operation for broader condition adaptability: Operation ranging from ‑40℃ to +70℃ covers various severe explosion‑proof sites with extreme cold, high temperature and sharp temperature fluctuation.
- Full‑isolation anti‑interference for high signal stability: Multi‑stage electrical‑isolation architecture mitigates complex industrial electromagnetic interference and ensures accurate instrument signals and stable equipment performance.
- Modular design for low‑cost maintenance: Standardized explosion‑proof construction with standardized installation and wiring. Replacement of faulty units needs no cabling or program modification and brings short downtime during technical retrofitting.
