Greenheck Fan Greenheck Centrifugal Inline Fans SQ/BSQ - Manual (Page 6)

6
Vari-Green
®
Motor - Model SQ
Greenheck’s
electronically
commutated (EC)
Vari-Green (VG) motor
combines motor
technology, controllability
and energy-efficiency into
one single low maintenance
unit and is the industry’s first
fully controllable motor. When combined with
Greenheck’s SQ fans, all the CFM and static pressure
ranges of a belt drive can be attained with the
benefits of a direct drive.
The Vari-Green motor is available in:
• 1/6 - 3/4 horsepower 115 volt only.
• 1 horsepower 115/208-230 volt.
• 2 horsepower 208-230 volt.
All motors are available in a 50/60 Hz power.
Benefits
Operates on AC power that’s converted to DC—
providing a more efficient motor operation as
compared to an AC operation.
• The motor can attain up to 85% efficiency and
reduce energy consumption.
• Watt savings of 30-70% depending on RPM.
Note: As motor speed is turned down, efficiency stays
high as compared to an AC motor that decreases
dramatically.
• Operates cooler than a standard AC motor at lower
RPMs. A cooler motor has longer motor life and
reduces energy consumption.
• 80% usable RPM turndown vs. 30%. (chart at right)
• SQ fans with Vari-Green motors can provide all
the CFM and static pressure ranges of a
comparable belt drive.
• Maintenance costs are reduced as there are
no belts or bearings to replace and no pulleys
to adjust.
• Direct drive fans are often preferred where
maintenance access is difficult.
• The Vari-Green provides a solution for demand
controlled ventilation applications.
Vari-Green Advantages
• Initial cost is similar to a belt drive
• Lower operating cost
• No maintenance, no belts, pulleys or bearings
• Easy RPM adjustment
Vari-Green
®
Options
 






600
500
400
300
200
100
0
0 350
50% 75% 100%
1750 FAN SPEED (RPM)
INPUT POWER (W
ATTS)
  
SQ-120
with PSC
BSQ-120
Single Phase*
Not recommended
Energy Savings









SQ-120 with
* BSQ is a belt driven fan
The length of each curve indicates the practical turndown range.
Data is for 1/2 hp motors with load of 0.35 Bhp at full speed
Motor Turndown Comparison
Features
1. Dial on Motor Control - A potentiometer (dial on
motor control) is mounted on the motor for easy
speed adjustment for system balance. Simply turn
the dial there are no belts and pulleys to adjust.
2. Control Wire Inputs - the motor accepts a
0-10V DC signal from Building Automated
Systems, Vari-Green Controls or other
controls to adjust motor speed.
1
2
®
Comparisons: Belt, Direct Drive with PSC
and Direct Drive with Vari-Green
Analysis is based
on operating costs
for a period of three
years where the fans
operate continuously
at 1725 rpm, 24/7,
with an energy
rate of $0.10/kWh.
Maintenance on the
SQ-120 is estimated
at $65/yr.
Note: Example is
based on a relative
cost. Use and
installation variables
may produce
different results.
$ 2,500
2,250
2,000
1,750
1,500
1,250
1000
750
500
250
$ 0
BSQ-
120
Three Year Cost Comparison
Initial Cost
Maintenance cost over three years
Operating cost over three years
SQ-
120-A5
SQ-
120-VG
Constant Volume Life Cycle Analysis