Auto-Zone Control Systems Zoning Design Guide (Version 01B) - Manual (Page 22)

22 Auto-Zone Systems
Zoning Design Guide
System Installation
Mounting Of Controllers
All Auto-Zone Round Dampers or Rectangular Damper
Kits have the required controllers, actuators etc. fac-
tory mounted in an indoor rated control enclosure. If
you wish to use another manufacturers dampers for zon-
ing control you must purchase Zone or Bypass Pack-
ages from WattMaster. These are furnished without a
mounting enclosure. Most local codes require these
components be mounted in an enclosure. If yours does
not require this it is still strongly recommended that
you do mount them in an enclosure. Components that
are not in an enclosure are in danger of being damaged,
and are susceptible to dirt and moisture contamination.
You may furnish your own enclosure or one is avail-
able from WattMaster. The part number for the
WattMaster enclosure is EE000075-01. This is an in-
door rated enclosure. If the zone mounting location is
susceptible to water damage, watertight enclosures can
be purchased at any local electrical supply. Mounting
location for the controllers should not violate any lo-
cal, state or national codes.
System Wiring
Wiring requirements for Auto-Zone systems can be bro-
ken down into four main categories:
1.) Power Wiring
2.) Communications Wiring
3.) Controller Wiring
4.) Sensor Wiring
Each category should be thoroughly understood and
implemented in order to have a trouble free installa-
tion.
Power Wiring
All Auto-Zone devices are powered by 24 VAC. It is
possible to power the system using one or more com-
mon transformers or individual transformers for each
device. Possible problems you may encounter using
common transformers to power multiple devices are:
•
If polarity is not maintained between devices,
shorting of the transformer will occur resulting
in damage to the electronics.
•
When using one transformer to power multiple
devices it is possible to lose most or all of your
system if the transformer fails.
•
It is important when powering multiple devices
from one transformer that total VA load and
wiring voltage drops be taken into account for
proper sizing of the transformer and wire.
(See Table 3 on page 23)
It is therefore recommended that in most installations
individual transformers be installed for each device.
This will greatly reduce the possibility of errors and
possible damage to the system.
Power wiring should always be done in accordance with
any local, state, or national codes.
It is also important to note that THE HVAC UNITS
FACTORY TRANSFORMER SHOULD NEVER
BE USED TO POWER Auto-Zone devices! Normally
transformers on typical HVAC units are sized to only
handle the load of the units factory installed controls.
A separate transformer must be used.
Communication Loops
The Auto-Zone system utilizes two different commu-
nications loops. The Basic system uses a 9600 Baud
RS-485 communications loop (Local Loop) only. The
Plus system uses two different communications loops.
It has a 9600 Baud RS-485 communications loop (Lo-
cal Loop) like the Basic system but also has an RS-485
19200 baud communication loop (Network Loop) that
connects the Zone Managers together and connects the
CommLink II communications interface.