Flammable Products - KROHNE H250 M40 Supplementary Instructions Manual

H250 M40

2.4 Flammable products

Atmospheric conditions: Atmospheric conditions: Atmospheric conditions: Atmospheric conditions:
The standard atmospheric conditions under which it may be assumed that Ex equipment can be
operated are:
• Temperature: -20...+60°C / -4...+140°F
• Pressure: 80...110 kPa (0.8...1.1 bar) / 11.6...15.9 psi
• Air with normal oxygen content, typically 21%v/v
Ex equipment operating outside the standard temperature range must be tested and certified
(e.g. for ambient temperature range -40...+65°C / -40...+149°F).
Ex equipment operating outside the standard atmospheric pressure range and standard oxygen
content is not permitted.
Operating conditions: Operating conditions:
Operating conditions: Operating conditions:
The measuring unit of variable area flowmeters operate outside the standard atmospheric
pressure range, which means that explosion protection, regardless of the zone assignment, is
fundamentally not applicable for the measuring unit (piping).
WARNING!
Operation with flammable products is only permitted as long as no explosive fuel/air mixture
builds up inside of the piping at the same time the atmospheric conditions are exceeded.
The operator is responsible to ensure that the flowmeter is operated safely in terms of the
temperature and pressure of the products used. In case of operation with flammable products
the measuring units must be included in the periodic pressure tests of the piping.
When using the device version H250/C... (PTFE version, non-conductive) the minimum
conductivity of the media must be 10
11/2019 - 4007945001 - AD H250-M40 Exec Gc R01 en
DEVICE DESCRIPTION
-8
S/m, in order to avoid danger from electrostatic charge.
www.krohne.com
2
7