8
INM MTL831C Rev 7
5 .12 .2 Data Highway screen with an MTL5553
Hazardous area installation of the sensors or MTL831C/MTL831C-PS require the use
of an isolator/power supply such as the MTL5553.
The screen of a Data Highway cable between the MTL831C/MTL831C-PS transmitter
and MTL5553 isolator is earthed to a local instrument earth in the MTL831C/MTL831C-
PS’s field enclosure or the at the MTL5553’s enclosure.
The screen of a Data Highway cable between the MTL5553 isolator and the MTL838C
is tied to the “S” terminal of the Data Highway port on the MTL838C. The “S” terminal
is internally connected to the GROUND terminals of the MTL838C. The GROUND
terminals of the MTL838C must be earthed at a local instrument earth.
Figure 1 - Recommended Screen Earthing for MTL830C System when Using an
MTL5553 Isolator
5 .12 .3 Data Highway screen with no MTL5553
The screen of a Data Highway cable between the MTL831C/MTL831C-PS transmitter
and the MTL838C is tied to the “S” terminal of the Data Highway port on the MTL838C.
The “S” terminal is internally connected to the GROUND terminals of the MTL838C.
The GROUND terminals of the MTL838C must be earthed at a local instrument earth.
Figure 2 - Recommended Screen Earthing for MTL830C System when using an
MTL5553 Isolator
+
S
-
+
S
-
+
S
-
+
S
-
Optional
Second
MTL831C[-xx]
Analog
Transmitter
MTL838C[-xxx]
Data Highway
terminals
GROUND
terminals
+
S
-
Data
Highway
Local
Instrument
Earth
Internal connection
between Data
Highway Screen
terminal and
GROUND terminals
MTL831C[-xx] Analog
Transmitter
A B C D
CH 1
A B C D
CH 16
Sensor
Local
Instrument
Earth
Earth
Bar
Sensor
Screen
(Shield)
…...
+
-
+
S
-
+
S
-
+
S
-
+
S
-
Optional
Second
MTL831C[-xx]
Analog
Transmitter
MTL5553
Isolator/Power
Supply
MTL838C[-xxx]
Data Highway
terminals
GROUND
terminals
+
-
+
S
-
Data
Highway
Local
Instrument
Earth
Internal connection
between Data
Highway Screen
terminal and
GROUND terminals
Local
Instrument
Earth
MTL831C[-xx] Analog
Transmitter
A B C D
CH 1
A B C D
CH 16
Sensor
Local
Instrument
Earth
Earth
Bar
Sensor
Screen
(Shield)
…...
Summary of Contents for MTL831-PS
Page 16: ...12 INM MTL831C Rev 7 11 FM ATEX and IECEx Information...
Page 17: ...13 INM MTL831C Rev 7...
Page 18: ...14 INM MTL831C Rev 7...
Page 19: ...15 INM MTL831C Rev 7...
Page 20: ...16 INM MTL831C Rev 7...
Page 21: ...17 INM MTL831C Rev 7...
Page 22: ...18 INM MTL831C Rev 7...
Page 23: ...19 INM MTL831C Rev 7 12 CCC INFORMATION...
Page 24: ...20 INM MTL831C Rev 7...
Page 25: ...21 INM MTL831C Rev 7...
