Description
System Role and Integration
The 4D33900G19 serves as the primary auxiliary power conversion and distribution assembly within the Ovation Distributed Control System architecture, functioning as the critical link between facility AC power and the low-voltage DC requirements of control system components. As an auxiliary power supply module, it mounts within standard Ovation enclosures—typically on DIN rail assemblies—and provides the isolated, regulated 24VDC power required by I/O backplanes, communication modules, and field termination circuits.
This module occupies a foundational position in the Ovation power hierarchy, operating downstream of the main cabinet circuit breakers and upstream of the specific I/O and controller modules. Unlike the main Ovation controller power supplies that directly feed processor racks, the 4D33900G19 specifically addresses auxiliary power needs for distributed I/O chassis, relay output panels, and termination distribution panels, ensuring reliable operation of field interface electronics independent of controller power states.
Core Functionality and Signal Handling
The module accepts a wide-range AC input from 85 to 264 volts at 47-63 Hz, accommodating both North American 120VAC and international 220-240VAC standards without hardware configuration changes. This universal input capability eliminates the need for separate part numbers for different geographical regions, simplifying spare parts management for multinational facilities.
Internally, the power supply converts the AC input to two independent 24VDC outputs: a primary 300W output for main I/O backplane power and a secondary 200W output for additional auxiliary loads or redundant power paths. The dual-output architecture allows flexible power distribution strategies, enabling engineers to segregate critical I/O power from non-essential loads or to implement redundant power feeding schemes for high-availability applications.
The module incorporates active power factor correction and inrush current limiting to minimize disturbance to upstream electrical systems during startup. Short-circuit protection, overvoltage protection, and thermal shutdown features ensure that faults in field wiring or connected modules do not propagate back to the power supply or create safety hazards.
4D33900G19
Platform Heritage and Operational Benefits
As a component of the Westinghouse Ovation platform now maintained within Emerson’s automation portfolio, the 4D33900G19 reflects the industrial power supply design philosophy developed for continuous-duty power generation and process control applications. The unit is designated as discontinued by the manufacturer but remains essential for maintaining legacy Ovation installations where original power architecture must be preserved.
The DIN rail mounting configuration facilitates installation in standard industrial control cabinets without custom mounting hardware, while the compact form factor optimizes space utilization in crowded power distribution compartments. The 663W maximum input power rating provides sufficient capacity to drive fully loaded I/O racks while maintaining adequate headroom for transient current demands during module startup sequences.
Part 4: Technical Specifications
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Model Number: 4D33900G19
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Manufacturer: Westinghouse Electric Corporation (Ovation product line)
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Product Type: Auxiliary Power Supply Module
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Input Voltage Range: 85–264 VAC, 47–63 Hz (universal input)
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Maximum Input Power: 663W
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Maximum Input Current: 8.0A RMS
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Output 1 (Primary): 24VDC, 300W maximum
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Output 2 (Secondary): 24VDC, 200W maximum (varies by sub-revision)
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Mounting: DIN rail compatible (35mm standard)
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Efficiency: High-efficiency switching design with active PFC
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Protection: Short-circuit, overvoltage, overload, and thermal protection
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Operating Temperature: -10°C to +60°C (per industrial power supply standards)
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Storage Temperature: -40°C to +85°C
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Humidity: 0% to 95% RH (non-condensing)
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Dimensions (Approximate): 120mm × 52mm × 166mm (varies by sub-version)
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Weight: 0.8 kg to 1.0 kg (module only)
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Sub-Versions: Sub 13, Sub 14, and others (functionally similar)
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Certifications: CE, UL508 (per associated documentation)
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Status: Discontinued by manufacturer; available via secondary market
Part 5: Core Features & Customer Value
Universal AC Input Range: The 85-264VAC input capability eliminates the need for voltage-specific power supply variants or external transformers when deploying Ovation systems across different international electrical standards. For global power generation companies and engineering contractors, this universality reduces spare parts inventory requirements—one part number serves both 120VAC North American installations and 220-240VAC international sites, simplifying procurement and stocking strategies.
Dual-Output Power Architecture: The separate 300W and 200W 24VDC outputs provide engineering flexibility in power distribution design. Rather than loading a single bus, engineers can dedicate the primary output to critical I/O backplanes while reserving the secondary output for relay panels, communication modules, or redundancy schemes. This segregation prevents noise coupling between power-hungry relay loads and sensitive analog I/O circuits, improving signal integrity and reducing troubleshooting complexity.
Integrated Protection and Safety: The module incorporates comprehensive protection circuitry that guards against field wiring faults and module failures. Short-circuit protection on each output channel prevents single-point failures from collapsing the entire auxiliary power system, while thermal shutdown protects the supply itself from damage due to excessive ambient temperatures or blocked ventilation. These features reduce maintenance callouts and prevent catastrophic power supply failures that could disable entire I/O racks.
High-Density DIN Rail Mounting: The compact DIN rail mounting form factor maximizes power density within control cabinets, allowing installation in standard 35mm rail assemblies without custom mounting brackets or drilling. This design provenance facilitates rapid replacement during maintenance events—technicians can extract the failed unit and install a replacement without disturbing adjacent wiring or requiring specialized tools, minimizing mean time to repair (MTTR) during critical outages.
Legacy System Support: As a discontinued component specifically engineered for the Ovation platform, the 4D33900G19 provides essential sparing capability for mature installations. Facilities operating Ovation-based turbine control or process safety systems can maintain original power distribution architectures without immediate migration to newer power supply form factors, deferring capital expenditure until planned upgrade cycles while maintaining regulatory compliance and operational availability.
4D33900G19
Part 6: Typical Applications
Power Generation Ovation I/O Cabinets: The 4D33900G19 is extensively deployed in coal-fired, gas-fired, and combined-cycle power plants as the auxiliary power source for distributed Ovation I/O chassis. In turbine control cabinets, the dual outputs power the CBO (Controller Backplane) electronics and ROP (Relay Output Panel) simultaneously, providing clean 24VDC power to contactor coils and solenoid drivers isolated from the main controller power supplies.
Relay Output Panel Power Distribution: Within Ovation relay output configurations (ROP, RRP, RRB panels), this module provides the regulated 24VDC required by relay driver electronics and base module logic. The 200W secondary output is particularly suited for these applications where multiple relay coils must be energized simultaneously during sequencing operations, ensuring adequate current capacity without voltage droop that could cause inconsistent relay pickup.
Field Termination and Distribution Assemblies: In TND (Termination Distribution) panels and remote I/O installations, the power supply drives the logic circuits of input conditioning modules and communication interface cards. The wide input voltage range accommodates voltage fluctuations common in remote field panels fed from long cable runs or transformer taps, while the regulated outputs ensure stable logic levels for discrete input cards sensing field contact status.
Safety Instrumented System Auxiliary Power: While not safety-rated itself, the module provides auxiliary power to Ovation-based safety instrumented function (SIF) I/O modules in non-safety critical capacities—such as diagnostic monitoring and communication interfaces—leaving safety-critical power paths to certified safety power supplies. This separation ensures that maintenance activities on auxiliary systems cannot inadvertently compromise safety function availability.
Water Treatment and Balance-of-Plant： In demineralizer, cooling tower, and auxiliary boiler control cabinets, the 4D33900G19 powers the distributed I/O nodes that monitor pump status, valve position, and flow instrumentation. The high efficiency and low heat generation minimize cooling loads in unattended field enclosures, reducing HVAC requirements and improving reliability in harsh outdoor or semi-outdoor installations common in water treatment facilities.
