BALDOR
7
General Information
General
Information
Single Phase
Motors
General Purpose
Industrial Motors
Severe Duty
Motors
Large AC
Motors
Washdown Duty
Motors
Explosion Proof
Motors
Pump Motors
Light Industrial/
Commercial Motors
HVAC Motors
Motors misapplied in hazardous environments can cause a fire or explosion resulting in destruction of property, serious
injury or death. Only the end user or a qualified underwriter is to identify and select the proper class, group, division, and
temperature code motor to meet the requirements of each installation. Baldor personnel can advise what listings and approvals Baldor motors carry,
but cannot evaluate nor recommend what motors may be suitable for use in hazardous environments.
CAUTION!
1.
Hazardous Locations — For details on area classification and equipment suitability please consult NFPA70™ National Electric Code
®
Articles
500-516.
• Class I Group C — locations are those which contain flammable gas, vapor, combustible liquid produced vapor mixed with air that may
burn or explode, either having a maximum experimental safe gap (MESG) value greater than 0.45 mm and less than or equal to 0.75mm
or a minimum igniting current ratio (MIC ratio) greater than 0.40 and less than or equal to 0.80. Ethylene is a typical Group C gas. For
other substances in this group, please consult NFPA 497.
• Class I Group D — locations are those which contain flammable gas, vapor, combustible liquid produced vapor mixed with air that may
burn or explode, either having a (MESG) value greater than 0.75 mm
or a (MIC ratio) greater than
0.80. Propane is a typical Group D
gas. For other substances in this group, please consult NFPA 497.
• Class II Group E — locations with atmospheres containing combustible metal dusts such as aluminum, magnesium and their alloys or
other combustible dusts with particle sizes and conductivity that present similar hazards. For other substances and guidance relative to
this group, please consult NFPA 499.
• Class II Group F — locations with atmospheres containing combustible carbonaceous dusts with more than 8% entrapped volatiles. Coal,
carbon black, charcoal and coke dust are examples from this group. For other substances and guidance relative to this group, please
consult NFPA 499.
• Class II Group G — locations with atmospheres containing combustible dusts not included in Group E or F, including flour, grain, wood,
plastic and chemicals. For other substances and guidance relative to this group, please consult NFPA 499.
2.
Class II Temperature Codes are typically the lower of either the ignition temperature of the combustible dust that is present or 165°C. These
low surface temperature requirements (higher temperature codes) required in Class II F&G require that over temperature protection be used.
• Explosion-Proof Motors rated 1 1/2 HP or less have internally mounted automatic thermal overloads when indicated by suffix “A”. Caution
must be observed when applying these to machinery applications to prevent accidental injury should the thermal device automatically
reset and restart the motor.
• Explosion-Proof Motors rated 1 HP and larger without automatic thermal overloads have thermostats in the windings. These thermostats
are pilot circuit devices to be connected to the magnetic starter circuit.
3.
Surface temperatures of Baldor Explosion-Proof Motors will not exceed the following UL and CSA maximums under fault conditions. The “T”
Code identifies the maximum absolute motor surface temperature that will be developed under all conditions of operation.
• Division 1 considers external surface temperature and includes overloads and locked rotor conditions.
• Division 2 considers internal and external surface temperatures during normal operation.
T Code
Maximum Motor Surface
Temperature
ºC
ºF
T1
450
842
T2
300
572
T2A
280
536
T2B
260
500
T2C
230
446
T2D
215
419
T3
200
392
T Code
Maximum Motor Surface
Temperature
ºC
ºF
T3A
180
356
T3B
165
329
T3C
160
320
T4
135
275
T4A
120
248
T5
100
212
T6
85
185
4.
Stock Motors are not suitable for applications in temperatures below -25°C (-13°F). Custom motor designs available for applications in
temperatures down to -60C. Contact your Baldor Sales office for further information.
5.
All Explosion-Proof motors are supplied with Explosion-Proof UL and CSA approved conduit boxes as standard.
6.
Baldor-Reliance AC Explosion Proof Motors, on pages 66-76, are not approved for use on adjustable speed drives only. Inverter Duty
Explosion Proof motors (page 190) can be used. Custom Explosion proof ratings available, contact your Baldor-Reliance Sales Representative.
Explosion Proof motors in this catalog use the following symbols to designate their Division 1, Class and Group certification capabilities. These assignments are for
use with this version of the 501 catalog only.
XP Class & Group Symbol
Description
➀
Class ±, Group D
➁
Class ±, Group D, Class ±±, Group F & G
➂
Class ±, Group D, Class ±±, Group E, F & G
➃
Class ±, Group C & D
➄
Class ±, Group C & D, Class ±±, Group F & G
UL AND CSA EXPLOSION-PROOF CLASSIFICATIONS