1 ouput data banks – FEC AFC1500 User Manual

Page 53

AFC1500 Multi-2 Unit Hardware Manual (Rev2.1)

PAGE 5 - 9

Chapter 5: Control Interfaces

5.3.4.1 Ouput Data Banks

When working with the Discrete I/O interface, the output signals are programmed into
“Banks” of 32 output signals in up to 8 output “Banks” (Max. 256 outputs). If the required
output signals from the Multi-2 Unit exceed 32 signals, then Bank 2 can be programmed
with additional signals. If over 64 signals are required, Bank 3 can be programmed and so
on. These Output “Banks” can then be selected by the Data Select input signals. The Data
Select input signals 0, 1 & 2 together form a binary code to select up to eight (8) different
Data Banks. (See Table 3 below)

Note: Bank Select inputs do not function with any interface except the Discrete I/O interface.
When using Bank selects, it is recommended that the bank number be monitored to confirm
actual output status of shared discrete output points. This can be performed by using the
“Always On / Always Off” bits set-up in specific discrete output points when programming
the output points with the AFC User Console Software. For this function, program the
“Always On / Always Off” bits to mimic the Data Select input bits. “Always On” bits will turn
on the output in that particular Bank as soon as the bank is selected. “Always Off” bits will
turn off the output in the particular Bank which is selected. Using different combinations of
these bits programmed in an output in each Bank will allow monitoring of which Bank is
selected.
The number of discrete outputs used for this monitoring function depends on how many
Banks are required as shown below:

Number of Banks Required

Number of Discrete Outputs Required

for Monitoring Output Bank Status

1 (32 outputs)

0 or 1

2-4 (64 – 128 outputs)

5-8 (160 – 256 outputs)

Typically these “Always On / Always Off” bits are programmed in the last output points (Pins
30 -32 as shown on the previous page).

[Table 3] Output Data (BANK) Selection

Data Select 2

Data Select 1

Data Select 0

Output Data Bank

OFF