FLAME PROOF MOTORS EX (d)
Table : 1
|
Zone |
Classification
of area as per IS : 5572 ( Part 1 ) |
Selection of
electrical equipment based on IS : 5571 |
Zone
' 0 ' |
An area in which hazardous
atmosphere is continuously present. |
Generally use of electrical
equipment is to be avoided but when this is not practicable intrinsically
safe or pressurized electrical equipment may be permitted to be used in
such areas. |
Zone
' 1 ' |
Hazardous atmosphere is likely
to be present at any time under normal operating conditions. |
For this area, electrical
equipment used, must be in a flame proof enclosure type (Ex) d as
specified by IS 2148 |
Zone
' 2 ' |
In this area hazardous
atmosphere is likely to be present only under abnormal operating
conditions and for a short period. |
Rotating electrical machines
having sliding contacts, centrifugal switches etc. which is normal
operation can cause arcing must be enclosed in flame proof
enclosures. Apparatus with type of protection (Ex)e in
accordance with IS-6381 may be used without any special enclosure.
Apparatus having type of protection (Ex)n in accordance with IS:8289 are
also permitted for use. Three phase induction |
Table : 2
| Temp.
Class as per IS : 6381 & IEC 79-7 |
Ignition
Temperature - C |
| |
Above |
Upto
and including |
| T1 |
450 |
- |
| T2 |
300 |
450 |
| T3 |
200 |
300 |
| T4 |
135 |
200 |
| T5 |
100 |
135 |
| T6 |
85 |
100 |
Classification of Hazardous
Gases :
Hazardous gases have been classified in IS : 2148, VDE 0171 & 5572 (Pt 1)
and are associated only with flame proof enclosures. These gases are
listed in Table 3.
Note : Flame Proof motors are offered suitable for Gas Groups I, IIA & IIB
only. For gases not mentioned, please refer the relevant Indian Standards.
Table : 3
| Gas Group |
Gas or Vapour |
Temp. Class |
| I |
Methane ( Firedamp) |
T1 |
| IIA |
Ammonia |
T1 |
| |
Industrial methane* |
T1 |
| |
Carbon monoxide |
T1 |
| |
Propane |
T1 |
| |
Butane |
T2 |
| |
Benzene |
T1 |
| |
Cyclohexane |
T2 |
| |
Acetone |
T1 |
| |
Ethyl acetate |
T1 |
| |
Methanol |
T1 |
| |
Ethanol |
T1 |
| |
n-Butanol |
T1 |
| IIB |
1,3-Butadiene |
T1 |
| |
Ethylene |
T1 |
| |
Diethyl ether |
T4 |
| |
Ethylene oxide |
T1 |
| |
Coke-oven gas |
T1 |
| IIC |
Hydrogen |
T1 |
* Industrial methane includes
methane mixed with not more than 10% by volume of hydrogen.
Approval Certificates
:
Electric equipments used in Zone 1 must by tested by CMRI- Dhanbad.
Approval certificates are issued by
the relevant authorities given below on the basis of the test report issued by
CMRI. All BBL motors have been approved by the relevant authorities.
i.e. DGMS - Dhanbad
CCE- Nagpur
DGFASLI - Mumbai
All flame proof motors have Licence Mark IS 2148.
A DGMS identification mark must be fitted on the motor for Gas Group I or Oil
Mines application.
Special Features :-
| Voltage |
Single or
dual voltage from 110V to 660V |
| Frequency |
Ranging from 25Hz to 60 Hz |
| Attitude |
Higher than
1000M from mean sea level. |
| Output |
Dual output /Dual speed with
dahlander connection or separate winding. |
| Shaft |
Longer shaft
lesser diameter. |
| Construction |
B6, B7, B8, V1, V3, V5, V6,
B3/B5 |
| Anti
Condensation Heater |
For all
frame sizes. |
| Cable entry* |
Plug & socket arrangement
for all frame sizes. |
| Re-greasing
arrangement* |
For all
frame sizes above and including MJ 160 |
| Flameproof motor
for crane duty application can also be offered against enquiries. |
| *
Only for FLP motors |
|
