Device description – KROHNE H250 M40 ATEX II2G Ex i EN User Manual
Page 13

DEVICE DESCRIPTION
2
13
H250 M40
www.krohne.com
08/2012 - 4001481101 MA H250/M40-Ex-II2G-AD R01 en
Reference point consideration
Reference point consideration
Reference point consideration
Reference point consideration
The permissible product and ambient temperatures may be exceeded or undershot as long as
the permissible temperature range of the reference point of the display is not exceeded. The
following table contains the permissible maximum values at the reference point. Note:
• Reference point is the connection of the equipotential bonding conductor of the M40 indicator.
• The temperatures at the reference point are to be determined in the most unfavourable
operating situation.
• The required measuring uncertainty is max. 2K.
• Measuring conditions and results are to be permanently recorded in a suitable format.
• The measuring unit should be insulated properly.
Maximum permitted temperatures at reference point of indicator in °C
Design of
indicator
Component
Limit switch
P
i
[mW]
Permitted temperature range at reference point
T [°C] according to temperature class
TK T6
T5
T4 ... T1
M40./../K.
SC3,5-NO-Y
64
-20 ... +65
-20 ... +80
-20 ... +90
169
-20 ... +37
-20 ... +52
-20 ... +72
SJ3,5-SN
64
-20 ... +66
-20 ... +81
-20 ... +90
169
-20 ... +42
-20 ... +57
-20 ... +86
SJ3,5-S1N
64
-20 ... +66
-20 ... +81
-20 ... +90
169
-20 ... +42
-20 ... +57
-20 ... +86
I7S23,5-N
64
-40 ... +70
-40 ... +85
-40 ... +90
169
-40 ... +52
-40 ... +67
-40 ... +90
M40./../ESK4/K.
SC3,5-NO-Y
64
-20 ... +55
-20 ... +70
-20 ... +80
169
-20 ... +33
-20 ... +48
-20 ... +68
SJ3,5-SN
64
-20 ... +55
-20 ... +70
-20 ... +80
169
-20 ... +38
-20 ... +53
-20 ... +80
SJ3,5-S1N
64
-20 ... +55
-20 ... +70
-20 ... +80
169
-20 ... +38
-20 ... +53
-20 ... +80
I7S23,5-N
64
-40 ... +55
-40 ... +70
-40 ... +80
169
-40 ... +48
-40 ... +63
-40 ... +80
M40./../ESK4
ESK4
---
-40 ... +55
-40 ... +70
-40 ... +80
M40./../ESK4-T
ESK4 and I/O modul
---
-40 ... +52
-40 ... +67
-40 ... +77
M40./../ESK4-FF
ESK4 and ESK4-FF
---
-40 ... +36
-40 ... +51
-40 ... +76
M40./../ESK4-PA
ESK4 and ESK4-PA
---
AD_H250_M40_II2G_R01_en_4001481101_PRT.book Page 13 Wednesday, August 1, 2012 8:00 AM