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Roof Top Unit Overview (MAGNUM). Visit us at www.mcscontrols.com. Revision-10 - 1/1/2020. RTU Magnum. Joins the Magnum family of software: HVAC (and LWC) CENT REFR. All Magnum software is supported by:. MCS-Config which builds the units profile. RTU Magnum.
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Roof Top Unit Overview (MAGNUM) Visit us at www.mcscontrols.com Revision-10 - 1/1/2020
RTU Magnum • Joins the Magnum family of software: • HVAC (and LWC) • CENT • REFR All Magnum software is supported by: MCS-Config which builds the units profile.
RTU Magnum All Magnum software is supported by: MCS-CONNECT for Communications MCS-Connect will indicate the current state of the system as viewed in above screen or on your Keypad.
RTU Magnum Purpose • Purpose is to provide flexible control to roof top units that provide heating, cooling and dehumidification to a building. • Plus the necessary ventilation control of fans and dampers, to insure proper air quality and building pressure.
RTU Operation Steps • At Power Up • If the unit is not in a LOCKOUT condition, the system will determine if the supply fan can be started. If yes the fan will be started and no other functions can be initialized until flow has been established and the minimum supply startup time (setpoint #108) has passed. • Determine Building Mode The MCS-MAGNUM will determine the building mode as Occupied, Unoccupied, Override, or Morning Warm Up. • Determine Unit mode • The setting of the unit mode will enable the cooling, heating or dehumidification functions to be executed. The setting of the control mode will be based on the control sensor for the Ventilation Mode.
RTU Magnum Occupied/Unoccupied • Occupied can be indicated based on a schedule • or digital input • Unoccupied can be over ridden with an override • indicator Status: • Occupied, set point values. • Unoccupied, set point values adjusted with night set back • Override, same as occupied
RTU Magnum Warm Up Option A warm up can be initiated by either a schedule to indicate occupied or unoccupied and prior to moving to occupied mode, the system will provide heat to the building to enable a warm up period or by a sensor input selected by the Forced Warm Up cell.
MCS RTU Magnum • Supports up to 80 Relay Outputs • Supports up to 112 Sensors Inputs • Supports up 28Analog Outputs • Supports 255 Set points • Supports storage of last 100 alarms (plus extended info for safety alarms) • Supports 1008 History Samples for all inputs & outputs
RTU Magnum Safeties • All HVAC safeties & preventive action are active. • Individual safeties are provided for each fan, damper, etc. • Smoke & fire safeties also provide the ability to purge the building • Clogged filter safeties • Energy Recovery Wheel safeties
RTU Magnum Safeties & Faults • High Static Pressure • Low Static Pressure • Supply Fan VFD Fault • Exhaust Fan VFD Fault • Return Fan Fault • MOD Gas Alarm • No Ignition Alarm • SCR Heating Alarm • Clogged Filter Alarm • Energy Wheel Alarm (No Rotation) • Energy Wheel Alarm (Fault) • Smoke Alarm • Fire Alarm • Smoke Purge Alarm
RTU Magnum Compressor Types The compressor type is selected from a drop down list in the Cooling Information panel on the Magnum RTU screen.
RTU Magnum Modes Screen Shows General Settings in MCS-CONFIG, this includes mode of operation and sensor control, general & unit sensors, occupied control, and vestibule control. Modes of operation • Ventilation • Cooling • Heating • Dehumidification
RTU Magnum Modes of Operation • Control sensors can be selected from return, supply, zone or ambient sensors. Set points will enable the modes to be active or ‘Forced’ sensors can be used. • The control sensor for “Switch to Cooling/Heating’ based upon a set point will enable these modes to be entered or keep the unit in the Ventilation Only mode. • When the system is in the Cooling, Heating or Dehumidification mode, the sensor control for that mode is selected independently.
RTU Magnum Vestibule Control • Vestibule control is based upon the temperature control sensor. • Fan, Cooling & Heating can be controlled. • Set point #246 contains the heating target. If the vestibule temperature is below the heating zone the heating relay will be turned on. • Set point #247 contains the cooling target. If the vestibule temperature is above the cooling zone the cooling relay will be turned on. • If either the cooling or heating relays are on, the fan relay, if specified, will be turned on.
RTU Magnum Ventilation Mode Screen Shows Ventilation Settings in MCS-CONFIG
RTU Magnum Ventilation Information Individual control can be specified for: • Building PSI • Supply Fan • Exhaust Fan • Return Fan • Outside Air Damper • Exhaust Damper • Relief Damper • Outside Air Damper • CO2 Control • Energy Recovery Wheel • Smoke Indicators & Relays
RTU Magnum Ventilation Fan Options • Building PSI: control can be either Direct, Reverse, or Not Used • Supply Fan: (control on Duct Static PSI) • Always On ( applies only if Occupied) • Cycle (on if heating or cooling needed) • Set up as modulating or fixed on/off • Can have 1 or 2 fans There is a pre-delay, post delay on the supply fan. Once the supply fan is on there is a delay before cooling or heating are allowed to stage up . Exhaust Fan: (control on Building PSI) • Set up as modulating or fixed on/off Return Fan: (control opposite of supply fan) • Set up as modulating or fixed on/off
RTU Magnum Ventilation Damper Options Outside Air Damper: Set up as modulating or fixed on/off Control can be based upon: • Local minimum fresh air requirement • Level of CO2 • CFM (air movement) • Building Static PSI • Will provide economizer cooling as first stage of cooling if conditions allow. Report on Fault Detection & Diagnostics (based upon California Energy Commission requirements)
RTU Magnum FDD • Report on Fault Detection & Diagnostics (based upon California Energy Commission requirements) • Option, OAD Fault Detection & Diagnostic’ must be Enable. • Purpose is to track the OA damper changes & effect on the air temperature of the unit. • If the damper has not kept the air temperature within its control zone then this is considered a fault. • This will not have effect on the OA damper positioning. • Set points #251, delay, & #252 controls the temperature control zone.
RTU Magnum Energy Recovery Wheel • Purpose is to capture potential lost energy by using the leaving air temperature to precondition the incoming fresh air. • During the warmer seasons, the system pre-cools and pre-heats in the cooler seasons. • The Energy Recovery wheel relay can be active when the supply fan is on and the system is not in economizer (free cooling) state. • A Bypass Damper can also be controlled • When on for a given period of time a defrost cycle will be initiated if the outside temperature is less than the defrost temperature.
RTU Magnum Cooling Mode This mode is based upon the existing HVAC control functions to control compressors and their safeties. The controlling sensor is selected in the General Info screen.
RTU SUPPORTS: • 8 circuits • Various types of Compressors & refrigerant types • Etc. same as HVAC. Also added a Digital Scroll type of Analog Output. If selected, and compressor is off… output will be equal to .7vdc. When compressor called to run, analog output will vary between 1.5vdc to 5vdc output.
RTU Magnum Heating Mode • This mode provides either 1 or multiple steps of heating. • The controlling sensor is independent from other modes.
The types of heating can be: • Direct Fire (up to 6 valves) • Modulating Gas (up to 6 valves) • Modulating Hot Water • Split Manifold (up to 6 valves) • (above types of heating support Auxiliary Heating) • Modulating SCR (VFD, may not be used, & up to 30 steps of electric heating) • On/Off Hot Water (up to 30 steps) • Staged (up to 30 steps) If multiple steps, current step must be at maximum capacity before next step is allow to start.
RTU Magnum Condenser Info All condenser types & options are the same as HVAC.
RTU Magnum Dehumidification Mode • Area is too moist, humidity needs to be reduced. • In this mode a fixed number of cooling stages are indicated. • Cooling stages that have reheat capability are the first on. • Cooling will reduce the humidity in the air. If heating is required the cooling stages reheat will be used.
RTU Magnum Dehumidification Mode • The types of reheat are: • Modulating • Fixed Step (number will be provided) • None • A Return Air Bypass Damper can also be controlled. • If additional heating is required the heating specified for the heat mode can be used, this is an option.
RTU Magnum Humidification Mode Area is too dry, need to increase humidity. When the system is NOT in cooling mode, humidity can be increased by modulating a Steam/Mist valve. The control sensor is specified and based upon a set point, the associated analog VFD will be modulated.
MCS RTU Magnum • Provide an over view of the RTU capabilities. • Stress the various options & flexibility. • RTU is separate software but it has all of HVAC’s cooling, EXV & condenser control. • RTU supported by the common MCS Configuration & Communication programs.