Data Aire dara-4g2 - Overview and Features; System Overview; Key Design Features

4•dara-4g
2
User Manual
1. OVERVIEW AND FEATURES
Overview
dara-4g
2
is a Lead/Lag Rotation and Alarm Auto changeover control panel for up to four HVAC units.
ThenumberofHVACunittomaintainonlineandtoholdofineisprogrammedondara-4g
2
menus.
Routine lead/lag unit rotation can be set from 4 hours up to 30 days, or no rotation. Force rotation
setting allows user to manually advance the rotation schedule to the next desired lead/lag rotation
pattern. Each HVAC unit is controlled by a non-power relay contact. Unit status messages are con-
tinually scrolled on a front panel 4 rows 22 characters liquid crystal display (LCD). dara-4g
2
has two
levels of password to prevent an unauthorized access for service and for programming. dara-4g
2
has a manual diagnostic menu that allows user to test the control inputs and outputs. Four built-in
manual override switches allow the user to override the automatic functions in an emergency case
or a failure of the dara-4g
2
. An optional zone air temperature and humidity sensor allows dara-4g
2
to
monitor the zone air condition and controls standby unit based on a zone air temperature setpoint
(Temperature Assist Mode). An optional network communication card allows dara-4g
2
to interface
with a BMS via Modbus or BACnet network protocol to monitor and control the system.
Design Features
• Fusesprotected24VACpowerinput
• Built-inliquidcrystaldisplaywithsystemstatus
• PowerOn/Offslideswitch
• Fourcontrolrelayswith8ampnon-powercontrolcontacts
• Audiblealarmwithselectablesoundpatterns
• AformCsummaryalarmcontactsforremotealarmstatusmonitoring
• Forcerotationmenuforrotationpatternselections
• Fouralarminputsdrycontacts
• Unitsmanualbypassswitches
• Softbuttonsforprogramming
• Menusdriventoprogram
o Number of units connected
o Number of units on
o Lead unit selection
• Optionalzonetemperaturesensorformonitoringandcontrol
• Highzonetemperaturesetpoint
• Manualdiagnostictest
• Twolevelspasswordsforsecurity
• Dateandtimedisplaywithrealtimeclock
• Rotationscheduledisplay
• Currentunitsstatuswithleadunitindicator
• Historicaldataforalarmhistoryandunits’runtimes
• Silencealarmbuttontoresetalarmunits
• Unitsonfail-safe
• USBportforrmwareupgrade
• OptionalBACnetMSTP,BACnetIPandModbusRTUnetworkcardforBMSinterface