Trane VAV-UCM 4.2, Инструкция по установке и обслуживанию

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VAV-SVX01C-EN 7
General Information
UCM 4.2 Enhancements
• The enhanced VAV UCM is backward compatible with VariTrane® D VAV boxes (VXXD and
VXXE) VariTrac® dampers, and VariTrac II dampers.
• UCM 4.2 adds support for operation with VariTrane Series F valves (¼-turn blade dampers) via
90-second drive time.
• UCM 4.2 adds a second, C0
2
interfacing, mode of operation to the auxiliary analog input (TB3-
5). This is a 1 to 10 volt DC input with a mapping of input voltage to C0
2
output data value of
200 parts per million (PPM) of C0
2
per volt. The use of this new auxiliary analog input as an
interface to a C0
2
detector is mutually exclusive with the use of the input as auxiliary
temperature input. Therefore, the use of the C0
2
interfacing mode of operation is not
recommended for stand-alone applications requiring auto-changeover.
• UCM 4.2 adds a binary 24 VAC, dry contact input. It can be configured either as a generic input
or as an occupancy detector input.
• UCM 4.2 adds a VariTrac Bypass Damper mode of operation. In this mode, supply air
temperature and supply air pressure is made available on the Comm4 link. The damper position
is a Comm4-control parameter. A Comm4 configurable failsafe position was added. The supply
air temperature uses a new "S" input (TB3-7). The use of this new input is mutually exclusive
with the zone temp input (TB3-1).
• UCM 4.2 now assumes the hot water valve is closed after reset. This prevents a reset during hot
water override from causing the valve to stop moving. This also changes the behavior after
reset, when there is a reheat demand, the hot water valve now opens (from assumed closed
position) to the desired reheat position.
• In a wireless system, the hard-wired sensor can now be configured as not present. The hard-
wired sensor failures will not be reported as long as at least one wireless zone sensor is
reporting valid temperature values.
Note: This is an older wireless system that has been obsoleted and not the one discussed in the
wireless zone sensor section.
• For standalone units, series or parallel fan operation will use the unoccupied fan control when
the local unoccupied request (** function) is received. In UCM 3.3 and prior, the fan would
operate as if occupied during local unoccupied request.
• UCM 4.2 adds a local minimum heating flow set point. The use of and value of this set point
is configurable.
UCM 4.2 Backward Compatibility
UCM 4.2 can be used to replace UCM I, UCM II, and UCM III with no compatibility issues. However,
if the communicating device (i.e. Command Unit I or Comfort Manager™ I) is a COM 3 device (1992
or earlier), then you will need an upgrade chip. The Comfort Manager chip upgrade is Kit 1511 and
the Command Unit chip upgrade is Kit 1512.
UCM 4.2 Features
UCM Outputs
UCM Triac outputs for controlling a fan or reheat are rated at 12 VA each.
Wiring Diagram
Figure 3, p. 18 shows a typical wiring diagram for the redesigned UCM hardware. The new service
part number is BRD02806.