| Terminology...
|
| |
The following selection guide is designed to help
you determine the correct motor for your application. It is written in general
terms and is intended only as an aid. The customer is solely responsible
for the motor performance and suitability in applications for their use.
No application fitness approval is implied as that can only be determined
by the customer. If further assistance is required in selecting the proper
motor, please contact a Doig customer service representative. |
| AGENCIES:
|
| |
U.L. (Underwriters Laboratory) and CSA (Canadian Standards
Association)
Where applicable, our motors including Inverter Duty, have UL listing for
explosion proof enclosures, UL recognized construction for non-explosion
proof enclosures, and UL recognition as a motor/protector combination. Our
motors are also CSA certified for both explosion proof and non-explosion
proof enclosures. |
| BEARINGS:
|
| |
Motors come with either sleeve bearings, ball bearings, or
roller bearings. Sleeve bearings are more economical and quieter than ball.
Ball bearings carry heavier loads and can withstand more severe applications.
Roller bearings are used in large motors for belted loads. Belting data
must be provided on all belted applications. Standard horizontal motors
can be mounted in a vertical shaft down orientation (brakemotors exempt).
|
| BLUE
MAX¨ AND BLACK MAX¨ INVERTER DUTY RATED MOTOR APPLICATION INFORMATION
AND RESTRICTIONS: |
| |
General Information:
Variable torque ratings are suitable for operation from 0 to base speed.
Variable torque operation beyond base speed must be reviewed by your application
specialist.
BLUE MAX¨ and BLACK MAX¨ constant torque motors provide full rated
torque within their listed speed range, without exceeding their Class F
temperature rating on inverter power. Ratings in this catalog are based
on extensive testing with IGBT inverters, set at a minimum 3 KHz carrier
frequency, and are designed for operation at 150% of rated torque for one
minute, up to the base speed of the motor (overload capacity declines to
100% as the motor reaches maximum speed). These motors accommodate Constant
Horsepower (CHP) operation to 1-1/2 to 2 times base speed, subject to the
motor's maximum safe mechanical speed limit.
It is the responsibility of the startup personnel during commissioning of
the VFD/motor combination to properly tune the drive to the motor for the
specific application. The correct voltage boost and volts/Hz settings are
application dependent and unique to each motor. Procedures for these adjustments
should be in your VFD user manual. WARNING: Power factor correction capacitors
should NEVER be installed between the drive and the motor. |
| MAXIMUM
SAFE MECHANICAL SPEEDS: |
| |
General purpose three phase motors, operated on IGBT inverter
at 3KHz carrier frequency, are suitable for operation on variable frequency
drives per the following table. (X = Suitable) |
|
|
Direct-Coupled |
Direct-Coupled |
Motor
Frame |
RPM
3600 |
RPM
1800,1200,900 |
| 56-184 |
7200 |
5400 |
| 213-256 |
5400 |
4200 |
| 284-286 |
5400 |
3600 |
| 324-326 |
4500 |
3600 |
| 364-365 |
4500 |
2700 |
| 404-449 |
3600 |
2700 |
|
| |
Note: TEFC motors are limited to 4000 rpm.
Operation above 60Hz will increase motor noise, vibration, and reduce bearing
life. Do NOT exceed 100 degree C bearing hub temperature.
For belted loads do not exceed 60Hz speed by more than 25%. NEMA TS shafts
are not suitable for belted loads.
|
| GUIDELINES
FOR APPLICATION OF GENERAL PURPOSE THREE PHASE MOTORS ON VARIABLE FREQUENCY
DRIVES: |
| |
General purpose three phase motors, operated on IGBT inverter
at 3KHz carrier frequency, are suitable for operation on variable frequency
drives per the following table. (X = Suitable) |
| Enclosure |
Efficiency
|
Frame
|
Var.
Torq. |
2:1
Const. Torq. |
10:1
Const.
Torq. |
Maximum Cable Length (ft) @3KHz Carrier Frequency
230
Volt |
Maximum Cable Length (ft) @3KHz Carrier Frequency
460
Volt |
Maximum Cable Length (ft) @3KHz Carrier Frequency
575
Volt |
| Dripproof |
All |
56-326T |
X |
|
|
600 |
125 |
40 |
| Dripproof |
All |
364T-500U |
X |
|
|
1000 |
225 |
60 |
| TEFC |
Std |
56-326T |
X |
X |
|
600 |
125 |
40 |
| TEFC |
Std |
364T-449T |
X |
X |
|
1000 |
225 |
60 |
| TEFC |
Series
E |
143T-256T |
X |
X |
X |
600 |
125 |
40 |
| TEFC |
Series
E |
284T-326T |
X |
X |
|
600 |
125 |
40 |
| TEFC |
Series
E |
364T-445T |
X |
X |
|
1000 |
225 |
60 |
| TEFC |
XRI |
143T-145T |
X |
X |
X |
600 |
125 |
40 |
| TEFC |
XRI |
182T-256T |
X |
X |
X |
1000 |
225 |
60 |
| TEFC |
XRI |
284T-449T* |
X |
X |
|
1000 |
225 |
60 |
|
| |
*Except 400HP
NOTE: Higher carrier frequency limits allowable cable length. |
| ELECTRICAL
TYPE/STARTING METHOD: |
| |
Motors are either capacitor start, split phase, permanent
split capacitor, or three phase. Capacitor start motors have high starting
torque, high breakdown torque, and relatively low starting current. Split
phase motors have medium starting torque and medium starting current. Permanent
split capacitor motors have low starting torque and low starting current.
Three phase motors have high starting torque, extra high breakdown torque,
and typically very low starting current. |
| ENCLOSURE: |
| |
Motors are available in dripproof, totally enclosed, and explosion
proof enclosures.
Dripproof motors have open enclosures and are suitable for indoor use and
in relatively clean atmospheres. Dripproof motors have ventilating openings
constructed so that drops of liquid or solid particles falling on the machine
at an angle of not greater than 15 degrees from the vertical cannot enter
the machine.
Totally enclosed motors are suitable for use in humid environments or dusty,
contaminated atmospheres. Totally enclosed non-ventilated motors are NOT
cooled by external means. Totally enclosed fan cooled motors are cooled
by external means that are part of the motor but not in the internal workings
of the motor. Totally enclosed air over motors are totally enclosed non-ventilated
motors that need to be sufficiently cooled by external means, provided by
the customer.
Explosion proof motors are also totally enclosed fan cooled or non-ventilated,
but designed for applications in hazardous atmospheres which contain explosive
gases or dusts. Here is a brief description of the hazardous locations
of both gaseous and dusty atmospheres as classified by the National Fire
Protection Association's National Electrical Code and printed from the
handbook.
Class I, Group A - Atmospheres containing acetylene.
Class I, Group B - Atmospheres containing hydrogen, fuel, and combustible
process gases containing more than 30 percent hydrogen by volume, or gases
or vapors of equivalent hazards such as butadiene, ethylene oxide, propylene
oxide, and acrolein.
- Class I, Group C - Atmospheres containing ethyl ether, ethylene,
or gases or vapors of equivalent hazard.
- Class I, Group D - Atmospheres such as acetone, ammonia, benzene,
butane, cyclopropane, ethanol, gasoline, hexane, methane, natural gas,
naphtha, propane, or gases or vapors of equivalent hazard.
- Class II, Group E - Atmospheres containing combustible metal dusts
including aluminum, magnesium, and their commercial alloys, or other
combustible dusts whose particle size, abrasiveness, and conductivity
present similar hazards in the use of electrical equipment.
- Class II, Group F - Atmospheres containing carbonaceous dusts, including
carbon black, charcoal, coal, or coke dusts that have more than 8 percent
total entrapped volatiles, or dusts that have been sensitized by other
materials so that they present an explosion hazard.
- Class II, Group G - Atmospheres containing combustible dusts not included
in Group E or F, including flour, grain, wood, plastic, and chemicals.
Consult the National Electrical Code for more information on explosion
proof regulations.
Explosion proof motors are UL listed in Class I, Division 1 Group D and
Class II, Division 1 Groups F and G ratings; Class I, Division 1 Groups
C and D and Class II, Groups F and G (56/140) ratings; or Class I, Division
1 Group D only. |
| FREQUENCY/HERTZ: |
| |
The number of complete alternations per second of an alternating
current. Expressed in Hertz as 60 Hz, 50 Hz, or 60/50 Hz. |
| GENERAL
PURPOSE, DEFINITE PURPOSE, AND SPECIAL PURPOSE: |
| |
There are three groups of motors as defined by NEMA. They
are general purpose, definite purpose, and special purpose. General purpose
motors can handle a wide variety of applications. They have NEMA torque,
NEMA limited current, conservative temperatures, and rugged construction.
Special purpose motors are more economical than general purpose. They have
moderately high torque and are designed for specific loads. Definite purpose
motors are designed for a specific application. Often they are restricted
in use by their physical and electrical characteristics. Good examples would
be oil burner motors, condenser fan motors, and double shaft fan and blower
motors. |
| HORSEPOWER: |
| |
Motors are available from 1/12 to 600 horsepower. |
| MOUNTING: |
| |
There are several mounting configurations available: Rigid
base or resilient base for belted drive applications (the resilient base
also minimizes vibration and noise), C-Face, D-flange, P-Base, thru-bolt,
resilient ring (only), and belly band mount are for direct drive applications. |
| NEMA
DESIGN CODES - THREE PHASE: |
Design
Letter |
Starting
Torque |
Breakdown
Torque |
Starting
Current |
Slip
at
Rated
Load |
| A |
Normal |
High |
High |
Low |
| B |
Normal |
Medium |
Normal |
Low |
| C |
High |
Normal |
Low |
Low |
| D |
Very
High |
N/A |
Low |
High |
|
| NEMA
SERVICE FACTOR RATINGS: |
| |
The table below lists the NEMA service factors for single
phase, dripproof motors. Totally enclosed and explosion proof motors have
1.0 service factors, except where noted. |
| Single
Phase |
| |
NEMA SERVICE FACTOR @ RPM LISTED |
| HP |
3600 |
1800 |
1200 |
900 |
| 1/12 |
1.4 |
1.4 |
1.4 |
1.4 |
| 1/8 |
1.4 |
1.4 |
1.4 |
1.4 |
| 1/6 |
1.35 |
1.35 |
1.35 |
1.35 |
| 1/4 |
1.35 |
1.35 |
1.35 |
1.35 |
| 1/3 |
1.35 |
1.35 |
1.35 |
1.35 |
| 1/2 |
1.25 |
1.25 |
1.25 |
1.15 |
| 3/4 |
1.25 |
1.25 |
1.15 |
1.15 |
| 1 |
1.25 |
1.15 |
1.15 |
1.15 |
| 1.5
& Up |
1.15 |
1.15 |
1.15 |
1.15 |
|
| OVERLOAD
PROTECTION: |
| |
There are four choices in protection: manual (inherent type),
automatic (inherent type), thermostats, and none. A manual overload must
be physically reset to restart the motor. An automatic thermal overload
will stop the motor when it is overloaded or overheated and restart it after
the motor has cooled down. None means the motor has no protection. Thermostats
are embedded in the winding and connected to the motor starter control circuit. |
CAUTION NOTE !
A MOTOR WITH AN AUTOMATIC
RESET PROTECTOR MUST NOT BE USED WHERE AUTOMATIC RESTARTING (AFTER MOTOR
COOL-DOWN) WOULD ENDANGER PERSONNEL OR EQUIPMENT. SUCH APPLICATIONS SHOULD
USE A MANUAL RESET PROTECTOR. |
| PHASE/POWER
SUPPLY: |
| |
Is the power supply three phase or single phase? Most home
and farm applications require single phase motors, while most factories
and large commercial and industrial users require three phase motors. Single
phase motors can be used on three phase systems. Three phase motors, however,
cannot be operated from single phase systems. Motor damage may result. |
| ROTATION: |
| |
Most motors on this website are reversible by electrical reconnection
or by physical orientation. |
| SERVICE
FACTORS: |
| |
Motors are available in either NEMA or 1.0 service factors.
A 1.0 service factor motor will perform to its nameplate rating. A NEMA
service factor motor can exceed its horsepower rating periodically. (See
table under NEMA Service Factor Ratings.) |
| SPEED/RPM: |
| |
3600, 1800, and 1200 are the most common 60 Hz synchronous
speeds with the full load speed equivalents of 3450, 1725, and 1150. |
| VOLTAGE: |
| |
Standard voltages are 115V, 115/230V, 230V, 230/460V, 460V,
and 575V at 60 Hertz. Many of our ratings are 115/208-230V or 208-230/460V
at 60 Hertz. Dual voltage motors are easily reconnected from information
shown on the nameplate of the motor. Motors rated at 230 volts will operate
on a 208 volt network for most applications that have nominal starting torque
requirements. Starting torque and peak running torque at 208 volts will
be 20-25% less than at the 230 volt level. If the starting torque is more
than nominal, the next higher horsepower 230 volt motor should be used.
Motors nameplated 115/208-230 or 208-230/460 volts will operate successfully
at 208 volts. At 208 volts, the motors may not meet NEMA specifications. |
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