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Device description, 7 ambient temperature / temperature classes – KROHNE DK 37-H250 M8 ATEX II2G Ex i EN User Manual

Page 8

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DEVICE DESCRIPTION

8

DK37/M8 - H250/M8

www.krohne.com

09/2013 - 4000760402 MA DK37 M8 AD II2G R02 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

+239

1

+135

+275

+90

2

+194

2

T3...T1

+40

+104

+145

+293

+200

+392

+50

+122

+130

+266

+200

+392

+60

+140

+115

1

+239

1

+200

1

+392

1

+90

2

+194

2

+140

2

+284

2

1 Temperature resistance of the cable ≥ +80°C / +176°F
2 Temperature resistance of the cable ≥ +70°C / +158°F

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