Ingersoll-Rand ReliaTel, Manual, Page: 70 / 176

70 RT-SVD03L-EN
Table 24. Normal run: 12½ to 17½ ton units
Model
Variable Speed Compressor
SZVAV Supply Fan
Speed
MZVAV Supply Fan
Speed
Freq. Min
(Hz)
Freq. Max
(Hz)
Vdc Min Vdc Max
Min-Min
V
Max-Min
V
Min-Min
V
Max-Min
V
Fan Only
0 0 0 0 1.6 1.6 1.6 1.6
12½ 15 75 2.4 6.8 1.6 7.6 1.6 7.6
15T 15 70 2.4 6.36 1.6 7.6 1.6 7.6
17½ 15 75 2.4 6.36 1.6 7.6 1.6 7.6
Economizing Supply Fan Speeds on VSPD
Compressor Configured Units
This subsection covers expected supply fan (indoor
fan) speeds during economizing-only based cooling
efforts. When economizing is available and
economizing-based cooling efforts are able to meet
cooling demands without staging up compressor-
based cooling, compressor operation is inhibited.
When a call for cooling exceeds the available cooling
capacity that can be provided by the economizing-
based cooling alone, compressor based cooling
operation may be leveraged. When compressors are
enabled, the required minimum supply fan speeds for
compressor-based cooling have priority over supply
fan speeds covered in this subsection.
The DX inhibited (compressors off) economizing
supply fan speeds for all supported eFlex
™
variable
speed compressors are to be as defined in the
following table below.
Table 25. Fan speeds
Relia-
Tel
™ ™--
Product
Family
Tons
Supply Fan
Control Type
(s):
Economizing
Active Supply
Fan Speed (with
DX Cooling
Inhibited):
Prece-
dent
™
3, 4, 5
SZVAV and
MZVAV
53% Airflow (PWM
Duty Cycle: 53%)
Prece-
dent
™
6, 7½,
8½, 10
SZVAV and
MZVAV
50% Airflow (0-
10Vdc signal: 50%)
Voyager ™-
Light
Commer-
cial
12½,
15,
17½
SZVAV and
MZVAV
37% Airflow (VFD
Command: 1.6Vdc)
Ventilation Supply Fan Speeds on VSPD
Compressor Configured Units
This subsection covers expected supply fan (indoor
fan) speeds during active ventilation efforts. Active
ventilation supply fan speeds for all supported eFlex
™
variables speed compressors are to be as defined in the
following table below:
Table 26. Supply fan speeds
Relia-
Tel ™ ™
Product
Family
Tons
Supply Fan
Control Type
(s)
Active
Ventilation
Supply Fan
Speed (with no
active call for
cooling/
heating/
dehumidifica-
tion)
Prece-
dent
™
3, 4, 5
SZVAV and
MZVAV
53% Airflow (PWM
Duty Cycle: 53%)
Voyager ™
Light
Commer-
cial
12½, 15,
17½
SZVAV and
MZVAV
37% Airflow (VFD
Command:
1.6Vdc)
N No otte e:: The above required supply fan speeds are the
expected speeds while there is only a call for
ventilation, and while there are no calls for
cooling, heating or dehumidification. When
cooling, heating or dehumidification calls do
exist, the required fan speeds for those efforts
have priority over the supply fan speeds
documented within this subsection.
Multi-Zone VAV Cooling
(Traditional VAV)
Occupied DX & Economizing Cooling
Control
For normal cooling operation, the total cooling capacity
will be modulated in order to meet the user selected
Discharge Air Cooling Setpoint (DACSP).
If enabled, economizer cooling will be utilized as the
first stage of cooling prior to energizing the DX
capacity. Economizer cooling will modulate the
Outdoor Air (OA) damper to maintain the DACSP - as
on standard fixed speed compressor equipped units.
Once all economizing requirements have been met,
compressor operation will be enabled if the
economizer alone cannot meet the demand. Once
compressor operation is started, the VSPD compressor
will startup, following all startup requirements, and will
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