General Information - Carrier CCU Regelungshandbuch

1 - GENERAL INFORMATION

The CCU CONTROLLER is fitted as standard to Close Control Unit systems. Setting and display console equipped with a 160-character
LCD screen. The CCU CONTROLLER is equipped with a microprocessor and an expansion board to provide the following functions:
■ Filtration
Checking the pressure drop in the filters, by monitoring the air flow and fouling level.
■ Control function (Cooling Mode)
• Chilled water model:
Gradual opening of the three-way valve following an increase in temperature.
• Direct expansion model:
Triggering of one or more refrigerating stages following an increase in temperature. (Action on condensation unit).
■ Control function (Heating Mode)
- Hot water coil model:
Gradual opening of the three-way valve following a decrease in temperature.
- Electric heater model:
Triggering of one or two stages following a decrease in temperature.
■ Control function (Dehumidification Mode)
- Opening of a chilled water valve or triggering of refrigerating stages, following an increase in humidity.
- Triggering of heating mode if there is a drift in temperature.
- As an option, decrease in the air flow to increase the latent part of the cooling capacity.
■ Control function (Humidification Mode)
- Triggering of humidification following a decrease in humidity.
■ Fan control
- Management of operation and faults for a 1-speed fan or variable-speed control fan.
- Fan on/off via an outer contact, internal timer.
- Variable speed control via temperature or humidity control, or raised floor pressure, or for constant flow control.
- Time-limited post ventilation for an electric heater.
- Interlock the controls and controllers to operation of the fan.
- Shift in start-up if there are several units at the same site.
- Soft start of the ventilation if there is a variable air volume.
■ Safety and alarms
- Overheating thermostat (Manual reset) on the electric heater.
- Pressure sensor for checking the air flow and filter fouling (Thresholds interlocked to the variation in the air flow).
- Configurable alarm threshold for high and low temperature.
- Configurable alarm threshold for high and low humidity.
- Low supply air temperature limitation sensor (limitation of the cooling capacity).
- Water leak control.
■ Configurable potential-free (dry) contacts made available for:
- Critical fault summary: air flow, fan, compressors, clogged filter, temperature sensor.
- Non-critical fault summary: filter fouled, electric heater, humidifier, water leak, target temperatures exceeded, target relative
humidity exceeded.
■ Memorisation
- Memorisation of the last 20 faults with the date and time of each fault, plus the readings of all the analogue input values at the
time of the fault.
- Parameter setting memorisation in the event of a power failure.
■ Remote control
- Option of remote control.
■ Metering
- Option to display metering for:
- The number of operating hours for the fans, compressors, electric heater stages, the humidifier, the fault summaries sent with
individual reset of each meter.
- The number of compressor start-ups.
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