The Emerson ASCO 903267 (Part Number 885611 REV-A) is a sophisticated electronic control module designed specifically for the ASCO 7000 Series Power Transfer Switches. This board serves as the “brain” of the transfer switch, monitoring utility power sources and managing the seamless transition to emergency backup power.
Product Parameters (Datasheet)
- Model Number: 903267
- Part Number: 885611 REV-A
- Series Compatibility: ASCO 7000 Series Automatic Transfer Switches (ATS)
- Input Voltage: Compatible with standard ATS control voltages (120V – 480V systems via sensing transformers)
- Logic Type: Microprocessor-based digital control
- Revision: Rev-A (Optimized hardware architecture)
- Communication: Supports serial communication and network interface integration
- Status Indicators: Onboard diagnostic LEDs for power, transfer status, and fault alarms
- Protection: Surge-suppressed inputs and outputs for industrial environments
- Operating Temperature: -20°C to +70°C (-4°F to 158°F)
Country of Origin
This control board is engineered and manufactured by ASCO Power Technologies (a brand of Emerson/Schneider Electric) in the USA, ensuring compliance with strict UL and National Electrical Code (NEC) standards.
Application Fields
The ASCO 903267 module is a critical component in mission-critical power systems, including:
- Data Centers: Managing instantaneous power switching to prevent server downtime.
- Healthcare Facilities: Ensuring life-support systems remain powered during utility outages.
- Telecommunications: Maintaining 24/7 uptime for cell towers and switching hubs.
- Water Treatment: Controlling emergency power for essential pumping and filtration.
- Commercial Infrastructure: Oversight of emergency lighting and fire safety systems in high-rise buildings.
Product Usage Instructions
- Installation: Ensure the ATS is completely isolated from all power sources (Normal and Emergency). Slide the board into the designated rack or mount onto standoffs.
- Wiring: Reconnect all ribbon cables and wiring harnesses according to the 885611 REV-A wiring schematic. Ensure all connectors are locked in place.
- Configuration: Use the ASCO handheld programmer or the onboard interface to set voltage thresholds, time delays, and engine exercise schedules.
- Testing: Perform a “No-Load” transfer test first to verify the logic initiates the generator start signal and contactor movement correctly.
- Maintenance: Periodically check the diagnostic LEDs. If the “Fault” LED is illuminated, consult the ASCO 7000 series manual for specific error codes related to this board revision.
Product Technical Description
Technically, the 903267 (885611 REV-A) functions as a sophisticated voltage and frequency sensing relay. It constantly samples the quality of the “Normal” source. If the voltage drops below a pre-set percentage (e.g., 85%), the board initiates a timer. If the outage persists, it sends a start signal to the standby generator and commands the high-speed transfer mechanism to move to the “Emergency” position. The Rev-A hardware includes improved noise filtering to prevent “ghost” trips caused by electrical interference in heavy industrial settings.
Q&A (Common Questions)
Q: Can I use this board in a 4000 Series ATS? A: No, the 903267 is specifically engineered for the 7000 Series architecture. Using it in other series may cause communication errors or hardware damage.
Q: Does this board require a separate battery? A: It typically draws power from the ATS control transformer, but it may interface with a battery-backed engine start circuit to maintain logic during the “dead time” of a transfer.
Q: What should I do if the transfer switch fails to return to the Normal source? A: Check the “Normal Source Acceptable” LED on the 903267 board. If it is not lit, the board is sensing that the utility power is still outside of safe operating parameters.
Q: Is this board field-repairable? A: Due to the safety-critical nature of power transfer, ASCO recommends replacing the entire 885611 module rather than attempting component-level repairs.
Similar Model Recommendations
- ASCO 903266 (Basic logic variant)
- ASCO 885611 REV-B (Later hardware revision)
- ASCO Group 5 Controller (Legacy series replacement)
- ASCO 7000 Series Communications Module (Network add-on)
- Emerson/ASCO 920 series monitoring board
For more information on the Emerson ASCO 903267 and our full inventory of power management components, please contact our technical support team.
