Description
1. At-A-Glance Executive Brief
- Model: 1797-PS2E2
- Brand: Allen-Bradley
- Part Type: Intrinsically Safe Power Supply (FLEX Ex I/O)
- Lifecycle Status: Mature / Legacy Support Phase
- System Compatibility: FLEX Ex I/O Platform (Bul. 1797)
- Weight: 7.7 kg (17 lbs)
2. Technical Introduction
Plant operators managing hazardous atmospheres frequently encounter severe space and cabling constraints when routing signals from safe-area marshalling panels through heavy conduit into Zone 1 locations. Relying on aging legacy infrastructure heightens the risk of unexpected component failure and extended downtime during critical production cycles.
The Allen-Bradley 1797-PS2E2 resolves this constraint by delivering a direct-mount, 24V DC power supply engineered specifically for the FLEX Ex I/O product line. Featuring built-in galvanic isolation, this unit eliminates the requirement for separate external intrinsic safety barriers while supplying four independent output channels to local node racks. It mounts directly inside hazardous areas (Class I, Div 1 / Zone 1), streamlining physical architecture and reducing wiring footprints.
3. Core Technical Specifications
| Parameter | Value |
| Input Voltage Range | 18–32V DC |
| Input Current | 3.1–1.6 A |
| Output Channels | 4 independent channels |
| Output Power per Channel | 8.5W (Total 34W max) |
| Output Voltage (U_o) | < 9.5V |
| Output Current (I_o) | < 1 A |
| Power Dissipation | 21 W |
| Operating Temperature | -20°C to 70°C |
| Enclosure Protection | Flame-proof enclosure (Ex de [ib] IIC T4 Gb) |
| Dimensions | 140 mm x 174 mm x 280 mm |
4. Field Engineer’s Tech Notes
- Thermal Load and Enclosure Heat Dissipation: Because this unit dissipates roughly 21W internally inside a flame-proof housing, verify that cabinet internal temperatures never breach the 70°C ceiling. Overloading channel capacitance beyond the specified limit (< 500 nF for IIC) triggers internal fault protection and drops the node.
- RI/Shield Grounding Integrity: Galvanic isolation relies heavily on proper chassis bonding to local earth studs. Omitting the dedicated DIN rail lock or failing to tie the ground lug directly to the local equipotential mesh will introduce common-mode noise and trip transient error states on the backplane communication loop.
5. Adaptive QA & Testing Protocol
Every pre-owned or surplus 1797-PS2E2 unit undergoes a rigorous bench validation before leaving our warehouse. Our testing protocol includes applying a stepped 18–32V DC input sweep while tracking dual-feed redundancy behavior. We load each of the four output channels to verify steady-state current delivery below safety thresholds, measure AC ripple under load to ensure it stays well within tolerances, and test galvanic isolation resistance using a high-pot tester. Comprehensive test reports and high-resolution inspection videos are available upon request prior to dispatch.
6. Buyer’s FAQ
- What warranty is included with this power supply?All units carry a comprehensive 12-month operational warranty covering both hardware functionality and compliance with baseline performance parameters.
- Is this unit supplied as New Surplus (NSFP) or refurbished?We stock both factory-sealed New Surplus (NSFP) and fully bench-tested refurbished variants. Condition status is explicitly verified on your commercial quote.
- Will this directly replace an older revision without changing the backplane?Yes. The 1797-PS2E2 maintains absolute form-factor and pin-compatibility across legacy FLEX Ex rack assemblies, permitting direct drop-in replacement during maintenance windows.
