Description
Telkoor CPCI-AC-3U-250 | 250W CompactPCI AC Power Supply
Dynamic Product Introduction
Embedded industrial computer racks running mission-critical telecommunications, defense, or automation control workloads require robust, hot-swappable power architecture that never blinks. The Telkoor CPCI-AC-3U-250 is engineered precisely for these environments, supplying a steady 250 watts of continuous power across a standardized 3U form factor.
Honestly, dealing with a failing power rail in a legacy CompactPCI chassis can bring an entire test cell or telecom node down instantly. This unit’s parallel converter topology—dedicated separately to the low-voltage high-current rails—ensures maximum current draw flexibility without thermal runaway, making it a reliable drop-in swap when older chassis power supplies give out.

AC-3U-250
Key Technical Specifications
| Parameter | Specification Detail |
| Input Voltage Range | 85 to 264 VAC Wide-Range (47–63 Hz) with Active PFC |
| Continuous Output Power | 250 Watts |
| Form Factor & Size | 3U Height, 8HP Width, 160 mm depth (CompactPCI format) |
| Bus Compliance | PICMG 2.11 Power Interface Specification |
| Backplane Connector | Standard 47-pin Positronic (or equivalent) cPCI connector |
| Redundancy & Hot Swap | N+1 Full Redundancy capability with active current sharing on V1/V2 |
| Operating Temperature | -5°C to +55°C (Full rating with no derating) |
| Safety & Emissions | UL, CSA, CE, CCC markings; meets FCC Part 15 / EN-55022 Class B |
Global Sourcing & Live-Test SOP
Sourcing legacy or operational-discontinued cPCI power modules demands stringent bench testing to verify regulation stability across multiple output rails under load. Our multi-point validation protocol ensures field dependability:
- Inbound Inspection: Units are checked for physical housing wear, front-panel extractor handle integrity, and clean pin-alignment on the rear 47-pin backplane connector.
- Cold & Hot Testing: The power supply is mounted to a custom 3U cPCI test chassis simulation rack. We step the AC input across low-line (85V) and high-line (264V) ranges to verify active Power Factor Correction (PFC) circuit operation.
- Rail Load Simulation: We apply dynamic loads across all standard output channels, monitoring ripple, noise, and voltage drop tolerances to guarantee tight regulation. Current-share lines are tested to verify proper load balancing during parallel N+1 operation.
- Thermal Soak & Prep: Units undergo a 4-hour burn-in under heavy load, followed by EEPROM parameter checks, terminal cleaning, and anti-static moisture-barrier sealing.
The Field Engineer’s Pitfall Guide
❗ Backplane Pin Oxidation: Repeatedly hot-swapping modules into older, dusty chassis racks can leave micro-deposits or cause pitting on the 47-pin connector blades, leading to intermittent contact on sense lines or current-share buses.
❗ Blindly Ignoring Minimum Airflow Requirements: Even though these units feature internal cooling management or rely on chassis cooling fans, blocking adjacent slot ventilation or running them in dead-air enclosures will trip internal thermal protection shutdowns.
❗ EEPROM Configuration Mismatch: Specialized system configurations rely on the onboard EEPROM for hardware status reporting to the system slot; replacing a custom-coded unit with a generic off-the-shelf variant can occasionally throw system management alerts in proprietary chassis monitoring software.
Intent-Driven FAQ
Can the CPCI-AC-3U-250 be hot-swapped in a live rack?
Yes. The unit is fully compliant with the PICMG 2.11 standard, supporting hot-swap insertion and removal alongside active current sharing for N+1 redundant power setups.
Does this power supply require a minimum load to start?
No. Telkoor designed this model with zero minimum load requirements, meaning it regulates safely and cleanly even when connected rails are idling or drawing minimal current.
What causes the unit to shut down immediately under load?
sudden shutdown typically points to an overload condition tripping the over-current protection (OCP), an input voltage sag below 85 VAC, or an internal over-temperature event triggered by blocked airflow.
Is an external line filter required to meet EMC standards?
While the power supply incorporates internal filtering, meeting strict commercial or military EMC specifications (like FCC Class B or EN-55022 Class B) typically requires the chassis system to use a proper external AC inlet line filter.
What warranty is provided with surplus units?
Every unit delivered from our inventory is backed by a comprehensive 12-month operational warranty covering internal component health, regulation performance, and switching stability.


