KROHNE DK 37 NEPSI Ex i - Manual (Page 7)

DEVICE DESCRIPTION
2
7
DK37/M8 - H250/M8
www.krohne.com 09/2013 - 4002616801 AD DK37 NEPSI Ex ia R01 en
2.7 Ambient temperature / temperature classes
Because of the influence of the temperature of the product, no fixed temperature class is
assigned to variable area flowmeters. In fact, the temperature class of a device is a function of
the temperature of both the product and the environment. A distinction is made between devices
with signal output 4...20 mA and limit switches. There is no distinction between devices with one
or two contacts. The classification is outlined in the following tables.
The tables take into account the following parameters:
• Ambient temperature T
amb.
• Product temperature T
m
DK37/M8./../.. permissible medium and ambient temperatures
INFORMATION!
The maximum permissible product temperatures listed in the tables are valid under
the following conditions:
• The measuring device is installed and operated in accordance with the installation
instructions in the installation and operating manual.
• It must be ensured that the flowmeter is not heated by the effects of additional heat radiation
(sunshine, neighbouring system components) and thus operated above the permissible
ambient temperature range.
• Insulation must be limited to the piping.
Unobstructed ventilation of the indicator part must be ensured.
Temperature
-class Ambient temperature up
to Maximum permissible medium temperature
Type DK37/M8E/.. Type DK37/M8M/..K.
[°C] [°F] [°C] [°F] [°C] [°F]
T6 +40 +104 +60 +140 +85 +185
+50 +122 - - +85 +185
+60 +140 - - +70 +158
T5 +40 +104 +100 +212 +100 +212
+50 +122 +85 +185 +100 +212
+60 +140 +65 +149 +100 +212
T4 +40 +104 +135 +275 +135 +275
+50 +122 +130 +266 +135 +275
+60 +140 (+115) 1 +90 (+239) 1
+194
+135 +275
T3...T1 +40 +104 +145 +293 +200 +392
+50 +122 +130 +266 +200 +392
+60 +140 (+115) 1 +90 (+239) 1
+194
(+200) 1
+140
(+392) 1
+284
1 Product temperature not in parentheses: Temperature resistance of the cable ≥ +70°C / +158°F
1 Product temperature in parentheses: Temperature resistance of the cable ≥ +80°C / +176°F
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