Current Loop Transmitter Impedance; Removable Connector; Wiring Diagram - Automation Direct DL405 User Manual

4–8
F4-04ADS 4-Channel Isolated Analog Input
Current Loop
Transmitter
Impedance
Removable
Connector
Wiring
Diagram
See Errata Sheet
at the beginning
of this file for an
updated wiring
diagram. The
connections for
CH3 and CH4
are incorrect.
They require an
external power
supply. Also, the
new drawing
shows
connection
examples for
both 2-wire and
4-wire
transmitters.
Standard 4 to 20 mA transmitters and transducers can operate from a wide variety
of power supplies. Not all transmitters are alike and the manufacturers often specify
a minimum loop or load resistance that must be used with the transmitter.
The F4-04ADS provides 250 ohms resistance for each channel. If your transmitter
requires a load resistance below 250 ohms, then you do not have to make any
adjustments. However, if your transmitter requires a load resistance higher than
250 ohms, then you need to add a resistor in series with the module.
Consider the following example for a transmitter being operated from a 36 VDC
supply with a recommended load resistance of 750 ohms. Since the module has a
250 ohm resistor, you need to add an additional resistor.
R + Tr * Mr
R – resistor to add
R + 750 * 250
Tr – Transmitter Requirement
R w 500
Mr – Module resistance (internal 250 ohms)
Two-wire Transmitter
DC Supply
+36V
0V
The F4-04ADS module has a removeable connector to make wiring easier. Simply
remove the retaining screws and gently pull the connector from the module.
NOTE 1: Shields should be grounded at the signal source.
NOTE 2: Unused channels should have V & C & R of the channels jumpered together.
See NOTE 1
CH1
+
Voltage
–
Transmitter
See NOTE 2
CH2 Not Used
CH3
+
2-wire 4–20mA
–
Transmitter
CH4
+
2-wire 4–20mA
–
Transmitter
+
–
User
Supply
21.6 - 26.4 VDC
+ –
V
C
R
250 ohms
V
C
R
250 ohms
V
C
R
250 ohms
V
C
R
250 ohms
+
–
Module Channel 1
V
R
C
R
250 ohms
ANALOG
4 CHANNELS
F4–04ADS
0–10VDC
0–5VDC
1–5VDC
+10VDC
+5VDC
4–20mA
CH1
+V
CH1
C
CH1
R
CH2
Analog
+V
CH2
switch
C
CH2
R
CH3
+V
CH3
C
CH3
R
CH4
+V
CH4
C
CH4
R
24VDC 0.5A
24
V
0
V
INPUT