Simex SRP-N1186, User Manual

Page: 18 / 64

User manual - METER SRP-N1186
SRP-N1186 meter has no galvanic separation between measurement input and
RS-485 interface. If serial connection of multiple units is made or serial connection
with other device, without galvanic separation of RS-485 interface, is made then
RS-485 interface separators must to be used certainly (
Figure 4.22 , 4.23 ). If RS-
485 interfaces are isolated or not used then the separators are not necessary.
Figure 4.22. Serial connection of active 2-wire sensor with SRP-N1186 unit
and other current measurement device (e.g. PLC controller).
Figure 4.23. Serial connection of passive 2-wire sensor with SRP-N1186 unit
and other current measurement device (e.g. PLC controller).
If device B ( Figure 4.22 , 4.23 ) is equipped with galvanic separated input or if
different potentials between
A
and
B
devices signal grounds are allowed (e.g. if RS-
485 interface is separated or unused), current loop can be closed without separator
G
.
18
!
!
-
+
Current source
0 - 20mA or
4 - 20mA
12 11 10 9 8 7
Connected internally
G
galvanic
isolation
+
-
A
B
+
-
R
B
-
+
12 11 10 9 8 7
Connected internally
G
galvanic
isolation
+
-
A
B
+
-
R
B