Analog Current Input Modules
FEATURES
• Wide Variety of Input Ranges
• Standard Package and Pin-out
• Single 5V Power Supply
• 12-Bit Resolution
• Optical Isolation from Input to
Output
• Intermix With Digital Modules on
the Same Rack
• Meets the Requirements of IEEE
472
• UL, CSA, CE Certified (OpenLine only)
73L-II
73G-II
CIRCUITRY: Voltage Output
G5: 0-5A
1
CURRENT
SOURCE
5A SECONDARY
TRANSFORMER
RECTIFY,
FILTER,
AMPLIFY
VOLTAGE
CONTROLLED
OSCILLATOR
G5: 4-20mA
+
1
˜
CURRENT
SOURCE
–
R
X
FILTER &
BUFFER
2
2
AMP
OPTICAL
ISOLATION
V
S
+5V
3
DC/DC
CONVERTER
+5 V
SQUARE-
WAVE
OUTPUT
GROUND
3
10KΩ
4
5
OUTPUT
DRIVER
CIRCUIT
V
S
SQUARE-
WAVE
OUTPUT
GROUND
10KΩ
4
5
V
S-
V/F
OpenLine
®
I/O MODULE
PIN #
+
LOOP
SUPPLY
4-20mA
TRANSMITTER
TWISTED
PAIR
1
2
1
2
+
–
133Ω
ISOLATION
SIGNAL
CONDITIONING
AND
FILTER
CHANNEL A
5.23K
9 MODULE ID
I/O Modules
I/O
30
–
8 RXD
7 TXD
CH. A
A/D
CH. B
µP
OPTICAL
ISOLATION
+
+
LOOP
SUPPLY
4-20mA
TRANSMITTER
TWISTED
PAIR
3
4
3
–
4
133Ω
SIGNAL
CONDITIONING
AND
FILTER
10K
CHANNEL B
Vs
ISOLATED
DC/DC
CONVERTER
6 Vcc
5 GND
–
Vs
–
TERMINAL
BLOCK #
Grayhill, Inc. • 561 Hillgrove Avenue • LaGrange, Illinois
60525-5997 • USA • Phone: 708-354-1040 • Fax: 708-354-2820 • www.grayhill.com