Contrec 515, Operation Manual

Page: 22 / 92

Installation
14 515 HC04 - 8 June 2007
4-20mA Inputs
For an externally powered current loop, connect the transmitter to the input
terminals as shown in Figure 6. Refer to
Terminal Designations on page 12
for specific terminal numbers for this application.
Figure 6 Externally Powered Current Loop
The internal overload-protected power supply has sufficient power for three
current loops at 24V DC (more current loops can be supplied by using a
reduced voltage setting). Connect internally powered current loops as
shown in Figure 7.
Figure 7 Internally Powered Current Loops
RTD Input
The instrument uses 4-wire RTDs to provide optimum accuracy and
stability. It is not necessary to have equal cable lengths for the 4-wire RTDs,
but they should be no longer than 50 metres. It is also recommended to use
shielded twisted pairs.
+
-
Transmitter
Analog
Input
(AINPn)
+
-
15
+
+
-
Analog
Input
+
+
-
Analog
Input
Vo +8...24V DC
(AINPn)
(AINPn)
Transmitter
Transmitter