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ZONE MASTER with dap4 User’s Guide
1.0 Introduction
The Zone Master offers unit lead/lag, rotation and a teamwork control solution for Data Aire units.
The Zone Master consists of one Master Unit and up to fi fteen (15) Slave Units. Unit #1 is always
assigned as the Master Unit (U1). Units #2 through #16 are slave units. Zone Master control logic
is confi gured in the Master unit.
The Zone Master units are connected together in a daisy chain topology using the dap4 pLAN
communication port (see the dap4 Zone Master wiring connections on page 9).
Note: The Zone Master is optional and requires an Activation Code for each unit in the zone.
The Zone Master provides selectable logic choices as listed below:
• Auto Lead/Lag Standby Rotation
• Secondary Operating Schedule for Economical Control
• Activate Standby Unit on Selectable Alarm
• Turn Unit Off Selectable Alarm
• Zone Inhibit Control Preventing Units from Confl icting Operations
• Standby Unit Activation on Temperature Control
1.1 Logic
1.1.1 Auto Lead/Lag Standby Rotation and Temperature Assist Logic – provides a means to au-
tomatically rotate the designation of STANDBY among a group of units that must be ON based on
programmable schedule.
The user may assign a number of units to a zone where a number units must always be ON and
others in STANDBY or OFF. ON units will have a PRIMARY designation on their status page at
the Zone Master’s display screen.
ON units will have a ONbyZM (On by Zone Master) designation at status display.
STANDBY will have a STBbyZM (Standby by Zone Master) designation.
Units that are ONbyZM but do not display the PRIMARY designation, have been brought ON by
the Zone Master because of a temperature requirement or an alarm.
OFF units will have a OFFbyZM (Off by Zone Master) designation.
The OFF mode setting will cause the blower and all cooling, heating, dehumidifi cation and humidi-
fi cation functions to be held off regardless of the zone’s requirements. The main control display
will display the following message: OFFbyZM
The message will also be displayed in the summary page of the master unit (such as – Status:
OFFbyZM).
