Digital Output - ABB Symphony Harmony Series Instruction

R E D U N DA N T
A IN -2 20 B A S E
+ 24 V
+ 24 V
+
4-20 m A
LO O P
–
Figure 4-6. AIN-220 Block - Current Mode (RFP Powered)

Digital Output

WBPEEUI240751C0
+
C H 1 A M P
–
•
•
•
+
C H 16 A M P
–
A
B
B
A
+
C H 1 A M P
–
•
•
•
+
C H 16 A M P
–
For digital output capable blocks, channels are directly wired
in parallel to both I/O modules (Figs.
short across an output of one I/O module due to an I/O block
fault will not allow the output to switch off. There are no
detectable channel failures for the digital outputs of DIO-400
and DOT-100 blocks.
The DOT-120 block has readback circuitry to monitor actual
outputs. If there is a difference between the actual output and
the read back output, the channel will be marked as suspect.
For the DOT-120 block, failover will occur if the primary I/O
module has an output stuck closed, but the backup will be
unable to correct this condition.
A IN -22 0 M O D U LE
R E F 1
O P TO -
A /D
C O U P LE R
R E F 16
O P TO -
A /D
C O U P LE R
R E D U N DA N C Y L IN K
A IN -22 0 M O D U LE
R E D U N DA N C Y L IN K
R E F 1
O P TO -
A /D
C O U P LE R
R E F 16
O P TO -
A /D
C O U P LE R
4-9 through 4-12). A
Digital Output
H N E T
A B
1
C P U
•
A N D
•
H N E T
•
IN T E R FAC E
16
1
C P U
•
A N D
•
H N E T
•
IN T E R FAC E
16
T 0 3 24 2 A
4 - 9