Racal Instruments 1260-38T, User Manual

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1260-38T User Manual
Module Operation 3-2 Racal Instruments © 1998
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 0
00 2 (channel 2 of multiplexer 00) will
also close channel 0 01 2 (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.
Front Panel
Connectors
The 1260-38T front panel connectors are labeled J200 and J201.
The connector type is 5 x 32 (160-pin) DIN 41 612 male. The pin
numbering is shown in Figure 3-3.
The mapping of channel numbers to connector pins and the
available mating connector cable is given in Table 3-1.