Honeywell FC-FANWR-24R Fan Controller

Description

1. Core Overview & Positioning

2. Key Features & Functions

• Dedicated Fan Control Logic:​ Contains embedded application software with standard sequences for:
  • Start/Stop Control:​ With configurable start/stop delays and interlocks (e.g., proving fan status via a differential pressure or airflow switch).
  • Manual/Auto Modes:​ Local override capability.
  • Safety & Protection:​ Built-in logic for handling faults, such as failure to prove operation after a start command.
  • Automatic Restart Attempts:​ Configurable number of restart attempts after a fault.
• Optimized I/O Configuration:​ The I/O is fixed and purpose-built for fan control, typically including:
  • Digital Inputs (DI):​ For start/stop commands, manual auto/off/on switch, fire alarm/safety interlock, and fan proof​ (differential pressure or current sensing switch).
  • Digital Outputs (DO):​ A heavy-duty relay output​ (e.g., 5A, 250V AC) to directly control the fan motor contactor or starter. Additional auxiliary relay outputs for alarms or secondary control.
  • Analog Input (AI) — Optional/Model Dependent:​ Some variants may include an analog input for speed command (e.g., 0-10V from a BMS) if used with a Variable Frequency Drive (VFD).
• Standalone Operation:​ Can be programmed and operate independently of a central BMS. Its basic start/stop logic runs locally based on its physical inputs.
• BMS Integration Ready:​ Equipped with a C-Bus communication port​ (Honeywell’s high-speed peer network) to connect to an Excel 5000 network or a WEBs Supervisor. This allows for:
  • Remote start/stop and speed command.
  • Monitoring of run status, alarm conditions.
  • Integration into larger sequences (e.g., starting an exhaust fan when an AHU starts).
• Clear Status Indication:​ Features LEDs for power, communication, run status, and alarms.

3. Model Number Breakdown & Specifications

• Power Supply:​ 24V AC or 24V DC​ (standard for HVAC controls).
• Control Outputs:
  • Main Relay Output:​ SPST or SPDT relay, typically rated for 5-10A at 240V AC, capable of directly switching a fan contactor coil.
  • Auxiliary Relay Output:​ For alarm signaling or secondary interlocks.
• Inputs:
  • Digital Inputs (x3-5):​ Dry contact inputs (volt-free) for commands and status. Includes dedicated input for a fan proof switch.
• Communication:​ C-Bus port​ for networking with other Honeywell controllers and supervisors.
• Programming:​ Configured using Honeywell CARE​ software or similar tools to set parameters like time delays, number of restart attempts, and interlock logic.
• Mounting:​ DIN-rail mountable enclosure.
• Safety Rating:​ Inputs may be rated for connection to safety circuits (e.g., fire alarm contacts), but verification of local codes and the specific module’s ratings is required.

4. System Integration & Operation

• 1. A valid start command (DI closed) is given.
  2. Controller energizes its main relay output after any programmed start delay.
  3. The relay closes, powering the fan contactor, which starts the motor.
  4. The controller monitors the Fan Proof​ input (DI). It expects this contact to close within a set time (e.g., 30-60 seconds), proving that air is moving or the motor is running.
  5. If the proof is received, the fan runs normally. If not received, the controller de-energizes the output, signals an alarm, and may attempt a restart based on configuration.
• Integration into BMS:​ When connected via C-Bus, a central supervisor can send a digital command to the controller’s «Remote Start» point (mapped in software) and read its «Run Status» and «Alarm» points.

5. Typical Applications

• Exhaust Fan Control:​ For toilet, kitchen, or parking garage exhaust fans, with interlock to a fire alarm system.
• Supply/Return Fan Control in Small AHUs:​ As the primary fan starter and safety controller.
• Standalone Ventilation Fans:​ In commercial or industrial spaces where simple, reliable control is needed.
• Fan Coil Unit Control:​ As the fan speed controller for a 3- or 4-pipe FCU (often used in conjunction with a separate valve controller).