Nexus A1557 - Page 6

Document Ref: Nex8inst.doc/Rev0 09.07.00 Page 6 of 30 Originator MC Checked by AC__
1.1.7 Loop Card Expansion Motherboard
1.1.8 Programmable Expansion Boards
Up to 31 A1535 (relay) and A1536 (alarm) programmable expansion boards may be connected
to the Nexus 1-8 loop (A1557) panel. Two boards may be housed internally, the remainder
require other enclosures. Refer to the A1535/A1536 Installation & Commissioning Manuals
for further details.
(i) A1535 8 Way Programmable Input/Output Relay Board
The A1535 board provides 8 programmable inputs and 8 programmable relay circuit outputs.
(ii) A1536 8 Way Programmable Input/Output Alarm Board
The A1536 board provides 8 programmable inputs (0V switched) and 8 programmable alarm
circuit outputs.
Loop 3 Loop 4 Loop 5 Loop6 Loop 7 Loop 8
0V
5V
24V
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Loop 3 card slot
Loop 4 card slot
Loop 5 card slot
Loop 6 card slot
Loop 7 card slot
Loop 8 card slot
A1557 motherboard
connector