Trane IntelliPak 2 Series, Инструкция по установке, эксплуатации и обслуживанию

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started while the variable speed compressor speed is
simultaneously ramped back down to minimum. Note
that capacity overlap is typically provided between each stage of operation to provide continuous capacity
modulation and minimize compressor cycling between
stages.
Figure 12. eFlex™ variable speed compressor, IntelliPak controller sequences
N No otte e:: The number of compressor stages varies from 3
to 7 depending on eFlex™ unit size.
Single Zone Variable Air Volume
(SZVAV) Only
The IntelliPak controls platform will support Single
Zone VAV as an optional unit control type in order to
meet ASHRAE 90.1. The basic control will be a hybrid
VAV/CV configured unit that provides discharge
temperature control to a varying discharge air
temperature target setpoint based on the space
temperature and/or humidity conditions. Concurrently,
the unit will control and optimize the supply fan speed
to maintain the zone temperature to a zone
temperature setpoint.
Supply Fan Output Control
Units configured for Single Zone VAV control will
utilize the same supply fan output control scheme as
on traditional VAV units except the VFD signal will be
based on zone heating and cooling demand instead of
the supply air pressure.
VFD Control
Single Zone VAV units will be equipped with a VFD-
controlled supply fan which is controlled via a 0-10VDC
signal from the Rooftop Module (RTM). The VFD will
modulate the supply fan motor speed, accelerating or
decelerating as required to maintain the zone
temperature to the zone temperature setpoint. When
subjected to high ambient return conditions the VFD
will reduce its output frequency to maintain operation.
Bypass control is offered to provide full nominal
airflow in the event of drive failure.
Ventilation Control
Units configured for Single Zone VAV control will
require special handling of the OA Damper Minimum
Position control in order to compensate for the non-
linearity of airflow associated with the variable supply
fan speed and damper combinations. Units configured
for Traq™ with or without DCV will operate identically
to traditional units with no control changes.
Space Pressure Control
For units configured with Space Pressure Control with
or without Statitrac, the new schemes implemented for
economizer minimum position handling require
changes to the existing Space Pressure Control scheme
in order to prevent over/under pressurization. The
overall scheme will remain very similar to VAV units
with Space Pressure Control with the exception of the
dynamic Exhaust Enable Setpoint.
For SZVAV an Exhaust Enable Setpoint must be
selected during the 100% Fan Speed Command. Once
selected, the difference between the Exhaust Enable
Setpoint and Design OA Damper Minimum Position at
100% Fan Speed Command will be calculated. The
difference calculated will be used as an offset and
added to the Active Building Design OA Minimum
Position Target in order to calculate the dynamic
Exhaust Enable Target, which will be used throughout
the Supply Fan Speed/OA Damper Position range.
The Exhaust Enable Target could be above or below
the Active Building Design OA Minimum Position
Target Setpoint, based on the Active Exhaust Enable
Setpoint being set above or below the Building Design
Minimum Position at 100% Fan Speed Command. Note
that an Exhaust Enable Setpoint of 0% will result in the
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