GE DS3800NFLA1C1C

Key Technical Parameters

Advantages and Distinctive Features

• 5A Mechanical Relays: The DS3800NFLA1C1C delivers 5A continuous output capability (10A surge), making it suitable for driving 1/2 HP AC fans or multiple DC fans in parallel—a significant upgrade over the 3A base model.

• Reduced Thermocouple Count (4 channels): With only 4 temperature inputs, the DS3800NFLA1C1C dedicates additional processing power to tachometer signal conditioning, providing more stable speed readings in high-EMI environments.

• Enhanced Tachometer Processing: The Revision C firmware includes advanced debounce filtering, reducing false speed failure alarms caused by electrical noise or fan vibration.

• Improved Temperature Accuracy: The 16-bit ADC with enhanced cold-junction compensation provides ±1°C accuracy—double the precision of the base model’s 12-bit (±2°C) ADC.

• AC/DC Output Capability: Mechanical relays on the DS3800NFLA1C1C can switch both AC and DC fan loads, offering flexibility for mixed cabinet installations.

• Complete Galvanic Isolation: Relay outputs provide 2500V isolation between control logic and fan power circuits.

Typical Application Fields

• Turbine Cabinets with Few Temperature Sensors: Where 4 sensors monitor multiple fan zones, and speed feedback is critical.

• Safety-Critical Cooling Systems: Applications requiring immediate fan failure detection via tachometer feedback.

• High-Inrush Fan Applications: 5A relays with 10A surge handling support large AC fans or motorized blowers.

• High-EMI Environments: Mechanical relays provide superior isolation and noise immunity compared to solid-state alternatives.

• Retrofit Upgrades: Replacing older DS3800NFLA boards with the DS3800NFLA1C1C for higher current, better accuracy, and extended temperature range.

Comparison with Related Models

Selection Recommendations

• Choose the DS3800NFLA1C1C if:

  • Your fans require mechanical relay outputs (AC or DC) with high surge handling (up to 10A).

  • Your cabinet uses ≤4 temperature sensors but requires 8 fan outputs.

  • You need enhanced tachometer feedback reliability in high-EMI environments.

  • You want improved temperature accuracy (±1°C) for better thermal management.

  • Your installation environment ranges from -20°C to +65°C.

• Choose the DS3800NFLA (base) if: You need 8 thermocouple inputs, 3A relays, and have a climate-controlled environment.

• Choose the DS3800NFEE1C1B if: You need 5A relays but do not require tachometer feedback.

• Choose the DS3800NFIA1B1C if: You prefer solid-state DC outputs with tachometer feedback and autonomous fallback logic.

Critical Precautions

• ESD Protection: The DS3800NFLA1C1C contains sensitive ADC components. Always wear a grounded ESD wrist strap.

• Missing Thermocouple Channels: The DS3800NFLA1C1C has only 4 thermocouple inputs (channels 1–4). Channels 5–8 are physically absent and will not function—do not attempt to connect sensors.

• Relay Contact Wear: Mechanical relays are rated for 100,000 operations at 5A. For frequent cycling, consider derating or using solid-state alternatives.

• Inductive Load Derating: The 5A rating applies to resistive loads. For inductive fan motors, derate to 3.5A or use an external RC snubber across each relay output to suppress arcing.

• Tachometer Wiring: Use shielded twisted-pair cable for tachometer signals. The enhanced conditioning on the DS3800NFLA1C1C reduces noise sensitivity, but proper grounding is still essential. Connect shield to the designated terminal—not at the fan end.

• No Hot-Swap: Always depower the Mark V rack before inserting or removing the DS3800NFLA1C1C.

• Slot Assignment: Install in auxiliary I/O slots (typically slots 8–10). Do not install in CPU or analog input slots.

• CPU Dependency: Since the DS3800NFLA1C1C has no onboard logic, the Mark V CPU must process tachometer feedback and send fan commands. If backplane communication is lost, the board defaults to 100% fan speed—tachometer monitoring will be disabled in fallback mode.

• Firmware Compatibility: Revision C firmware is compatible with Mark V CPU firmware v4.0 and above. For v3.x systems, the enhanced tachometer filtering may be partially disabled—confirm compatibility before purchasing.