KNF MOTOR M 56 EX
Use
Translation of Original Operating- and Installation Instructions, english, KNF 121220-121648 02/19
5
2.4. Explanations on explosion-protection marking
2.4.1. Equipment groups
Equipment group I applies to products for use in underground
plants of mines and their above-ground systems which can be
endangered by methane and/or flammable dusts.
Equipment group II applies to products for use in the remaining
areas which can be endangered by an explosive atmosphere.
2.4.2. Equipment categories for gas
The equipment category describes the frequency and duration of
the occurrence of explosive atmospheres in an area.
Equipment
category
Description*
Design safety
1
Equipment for areas in which it is to be expected that a dangerous
explosive atmosphere will occur constantly, over longer periods or
frequently.
Very high
2
Equipment for areas in which it is to be expected that a dangerous
explosive atmosphere will occur occasionally.
High
3
Equipment for areas in which it is not to be expected that a danger-
ous explosive atmosphere will occur. However, if it does occur, then
only seldom and only briefly.
Normal
Tab. 3
*in accordance with 2014/34/EU
2.4.3. Temperature classes
The maximum surface temperature is the highest temperature
reached by a motor surface under the most unfavorable conditions.
The maximum motor surface temperature must always be lower
than the lowest ignition temperature of the gas or vapor-air mixture
in which it is used.
The maximum surface temperature results from the motor design
and is specified as the temperature class.
Temperature class
Max. surface tem-
perature [°C]
Ignition temperature
[°C]
T1 450
>
450
T2 300
>
300
T3 200
>
200
T4 135
>
135
T5 100
>
100
T6 85 >
85
Tab. 4
Equipment group I
Equipment group II
Maximum
surface temperature
Ignition temperature
Temperature class
