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User Manual 1260-38
Module Operation 3-2
pairs of interconnecting relays (1000, 1001,2000, 2001, …7000,
7001). This allows pairs of the module to be configured for four-
wire operation.
Two-Wire
Operation
Two-wire configuration gives the most flexibility as it allows all
channels (0000 through 0157, 1000 through 8000, and 9000
through 9007) to be selected.
Interconnecting relays (1000, 1001, 2000, 2001, …..7000, 7001)
permit linking of all the 1 x 8 multiplexers to give configurations
from sixteen 1 x 8 multiplexers up to one 1 x 128 multiplexer.
Example: Make a two-wire 1 x 32 using multiplexes 00,01,02,03
Close channels 1000, 1002 and 2002.
Four-Wire
Operation
Four-wire configuration permits four-wire closures only. Only even-
numbered multiplexers (00, 02, ….14) may be selected. Closing a
channel in an even-numbered multiplexer also closes the
equivalent channel in the adjacent odd-numbered multiplexer. For
example, closing Channel 0002 (channel 2 of multiplexer 00) will
also close channel 0012 (channel 2 of multiplexer 01).
The same applies to the interconnect relays (channels 1000, 1001,
2000, 2001, …..7000, 7001). Closing channel 1000 will also close
channel 1001). In four-wire operation, the interconnect relays
permit configurations of eight 1 x 8 multiplexers up to one 1 x 64
multiplexer.
Example: Make a four-wire 1 x 24 using multiplexers 00, 01, 02,
03, 04, 05
Close channels 1000 and 2000.
One-Wire
Operation
One-wire switching must be performed with the 1260-38
configured for two-wire operation. Each even-numbered
multiplexer includes a one-wire relay (channels 9000, 9001,
9007). This allows configurations from sixteen 1 x 16 multiplexers
up to one 1 x 256 multiplexer.
Example: Make a one-wire 1 x 96 using multiplexers 00, 01, 02,
03, 04, 05
Close channels 1000, 1002, 2000, 2002 and 3002.
When the one-wire channel is open, the one-wire common is
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