Marvair MPC-10 HVAC Controller  Marvair MPC-10 Controller

The Marvair MPC-10 is an HVAC controller designed to control up to ten air conditioners, that can be either single or dual compressor, for equipment enclosures. In addition to the control of the air conditioners, the MPC-10 provides alarms remotely, through BACnet or Modbus, and locally using a built-in Human Machine Interface (HMI). The controller is factory programmed with standard industry set points, but can be configured on site or remotely. Settings are retained indefinitely in the event of a power loss.

  • Control Up to Ten Air Conditioners in a Shelter
    The MPC-10 offers the ability to stage cooling and heating operation for both dual and single circuit PLC equipped units. This gives the controller a maximum of 20 stages of cooling for dual circuit units, 10 stages of cooling for single circuit units, and 10 stages of heating. 
  • Ease of Control and Configuration
    The MPC-10 comes standard with a 7-inch color touchscreen HMI which provides a user-friendly interface. From the main screen of the HMI the user can see room conditions, HVAC status for each unit, and change cooling/heating set points. The statuses that can be displayed for each unit are as follows: Cooling, Heating, Blower, Fault, Standby, Shutdown, and T-Stat Off. If a fault occurs an alarm window will pop-up that displays a description of the alarm, the time/date at which it occurred, and the current status of the alarm. Along with the pop-up an alarm button will appear which allows the user to minimize/maximize the alarm window. The alarms will be maintained until the fault is fixed and the alarm is cleared. 

    The initial setup of the MPC-10 will be done from the built-in HMI. During this process the user will input the number of units, whether the units are dual or singe circuit, and the desired communication protocol. Once the initial setup is complete all other parameters can be changed, at any time, from the 2nd page of the HMI (F2 Button) or remotely. 

Features and Benefits:


Programmable Logic Board with Lead/Lag Control

  • Balanced Use of Conditioning Equipment
  • Sequence the Operation of up to 10 PLC Based Units
  • Ensures Maximum Efficiency
  • Independent Economizer Control
  • Remote Communication (BACnet/Modbus)

Alarms and Lockouts

  • High Pressure Lockout (Both Circuits If Applicable)
  • Low Pressure Lockout (Both Circuits If Applicable)
  • Phase Alarm
  • Communication Alarm
  • Emergency Shutdown Alarm
  • High Shelter Temperature Alarm
  • Low Shelter Temperature Alarm

Specifications and Additional Features


Remote Communication Protocol

The Marvair MPC-10 comes standard with both BACnet and Modbus TCP/IP communication protocols and can be user selected in the initial setup menu.  Using these communication protocols allows the user to access and change various data points.

Read-Only Access:
  • Room Temperature
  • Room Humidity
  • Lead Unit
  • High Pressure Refrigeration Circuit A (For Each Unit)
  • High Pressure Refrigeration Circuit B (For Each Unit)
  • High Temperature Cut-Off (For Each Unit)
  • High Temperature Alarm
  • Low Temperature Alarm
  • Phase Fault (For Each Unit)
  • Low Pressure Refrigeration Circuit A (For Each Unit)
  • Low Pressure Refrigeration Circuit B (For Each Unit)
  • Emergency Shutdown (For Each Unit)
Read/Write Access:
  • Cooling Set Point
  • Continuous Blower
  • Cooling Stage Differential
  • Low Temperature Alarm Set Point
  • Y Fan Purge Time
  • Anti-Short Cycle Time
  • Thermostat Offset
  • Heating Set Point
  • Lead Swap
  • Heating Stage Differential
  • High Temperature Alarm Set Point
  • W Fan Purge Time
  • Lead Swap Period
  • AC Unit Shutdown (For Each Unit)

Thermostat

  • Cooling Set Point: 35°F through 95°F
    (1.7°C through 35°C) in 1° increments.
  • Heating Set Point: 35°F through 95°F
    (1.7°C through 35°C) in 1° increments.

Differential

  • Cooling Stage Differential: 1°F through 5°F
    (1° through 3°C) in 1° increments.
  • Heating Stage Differential: 1°F through 5°F
    (1° through 3°C) in 1° increments.

Incoming Power

  • 24 VDC

Minimum Ambient Temperature During Operation:

  • 30°F (0°C)

Maximum Ambient Temperature During Operation

  • 122°F (50°C)

Ease of Installation

  • The use of Siemens Profinet communication makes wiring simple. All communication between the HVAC units and the controller is handled over ethernet cables. The MPC-10 has eleven ethernet ports located at the bottom of the controller, one for each unit and one for remote communication. The order in which the units are connected does not matter.

Lead/Lag Operation

  • User selectable changeover from 12 hours to 10 days in 1-hour increments. If the lead unit loses power, the next available unit automatically becomes the lead unit with all the set points of the lead unit. Once a unit is locked out or losses power it is removed from the list of available units and will not be called for by the controller. When the unit is repaired/regains power it will be added back to the list of available units and can be called for by the controller. Additionally, a lead swap button can be found on the HMI allowing service techs to easily check the operation of each unit.

Alarms
Alarms can be viewed remotely via BACnet/Modbus, through an on-screen alarm window, and each unit contains a flash code on the PLC. There are two classifications of alarms. Unit alarms are specific to the unit. These alarms will start with the unit designator followed by the alarm (E.g. Unit 3 Phase Fault). Shelter alarms apply to the entire building. These alarms include high/low temperature alarms.

Unit Alarms

  • High Pressure Switch A – The refrigerant pressure on side “A” has exceeded the set point pressure twice in a cooling cycle. The air conditioner will shut down and notification will be sent that there is a high-pressure “A” alarm.
  • Low Pressure Switch A – The refrigerant pressure on side “A” has dropped below the set point pressure twice in a cooling cycle. The air conditioner will shut down and notification will be sent that there is a low-pressure “A” alarm. 
  • High Pressure Switch B (If Applicable) – The refrigerant pressure on side “B” has exceeded the set point pressure twice in a cooling cycle. The air conditioner will shut down and notification will be sent that there is a high-pressure “B” alarm. 
  • Low Pressure Switch B (If Applicable) – The refrigerant pressure on side “B” has dropped below the set point pressure twice in a cooling cycle. The air conditioner will shut down and notification will be sent that there is a low-pressure “B” alarm.
  • Phase – This is activated when the unit is out of phase. If this alarm is activated the alarm window on the HMI will pop-up and have a message reading “Unit X Phase Fault”.
  • Emergency Shutdown – This alarm is activated when the unit is shut down by the user via remote access or thru the HMI.
  • High Temperature Cut-Off (If Applicable) – This is activated when the heater in the unit exceeds the set point. Once this occurs the heater will be unavailable and an alarm will be visible on the HMI. 
  • Communication – This is activated when a unit loses communication to the main controller. If this alarm is activated the alarm window on the HMI will pop-up and have a message reading “Unit X Communication Fault”. In the event of this alarm the controller will not call for the affected unit.

Shelter Alarms

  • Low Building Temperature – Activated if the temperature in the building drops to the selected temperature. Factory default is 50°F but can be changed from the parameters page of the HMI in 1° increments between 30°F and 95°F. If this alarm is activated the alarm window on the HMI will pop-up and have a message reading “Low Temperature Alarm”.
  • High Building Temperature – Activated if the temperature in the building reaches the selected temperature. Factory default is 90°F but can be changed from the parameters page of the HMI in 1° increments between 30°F and 95°F. If this alarm is activated the alarm window on the HMI will pop-up and have a message reading “High Temperature Alarm”.

For detailed specifications, performance, and efficiency information, download the Product Data Sheet from the document list on this page.