iWorx® MPU2
32
505-009, Effective: June 30, 2015
© 2015 Taco Electronic Solutions, Inc.
You configure the occupied and unoccupied times that are used in determining the current operating mode of the con-
troller when it is running the backup schedule. By default, both the unoccupied and occupied times are set to zero,
which disables the local backup schedule. This causes the controller to default to the occupied mode of operation when
communications are lost to the LCI for 10 minutes or longer.
Runtime Accumulations
The total runtime is accumulated for the heating, cooling, and fan outputs. The runtimes can be used to indicate that
maintenance is required on the equipment controlled by these outputs. An operator or maintenance personnel can
reset the runtime once servicing has been performed.
Alarms and Events
The MPU2 detects certain alarm conditions and sends them to the LCI. Before this can occur, the MPU2 must have
been configured by the LCI.
Digital Input Alarms
The MPU2 monitors the status of the digital inputs and generates alarms for the following events:
• Fan Failure
• Smoke Detect
• Mixed Air Low Limit
• Dirty Filter
• CO
2
Alarm
Supply Air Temperature Alarms
The following alarms can be generated based on supply air monitoring.
• Cooling Failed
• Heating Failed
• Heat Stuck On
Maintenance Alarm
A MPU2 provides programmable run limits for generating runtime maintenance alarms. When the cooling runtime,
heating runtime or fan runtime exceeds these limits, a maintenance alarm is sent to the LCI.
Automatic Configuration
The MPU2 and iWorx® Local Control Interface (LCI) use a self-configuring network management scheme requiring no
external tools, binding, or L
ON
W
ORKS
knowledge. The LCI recognizes and configures the MPU2 when the controller’s
service pin is pressed. The controller’s status light flashes green until the controller is configured, and is solid green
after the controller is configured. Once the service pin has been pressed, no further action is required by the user; the
controller is fully accessible to the LCI. Users may bind to SNVTs on the MPU2 with LNS or other L
ON
W
ORKS
tools if
they wish.
The LCI also provides network supervision of the MPU2. The LCI periodically sends a "ping" message to the MPU2,
which elicits a response. If the response fails, an alarm is displayed on the LCI. The LCI also uses the "ping" message
to refresh the occupancy mode and other system wide data.
