M&C TechGroup MP47 Ex Operator's manual - Handbuch (Seite 33)

Diaphragm Pumps PJ19424-726 Use
Translation of Original Operating- and Installation Instructions, english, KNF PJ19424-726 01/13 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 Areas in which it is to be expected that a dangerous explosive at-
mosphere will occur constantly, over longer periods or frequently. Very high
2 Areas in which it is to be expected that a dangerous explosive at-
mosphere will occur occasionally. High
3 Areas in which it is not to be expected that a dangerous explosive
atmosphere will occur. However, if it does occur, then only seldom
and only briefly. Normal
Tab. 3 *in accordance with EN 1127-1
2.4.3. Temperature classes
The maximum surface temperature is the highest temperature
reached by a pump surface under the most unfavorable conditions.
The maximum pump 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 pump 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