1781-A8AProduct Family: Discrete I/O Mounting Boards
- Logic supply +Vcc (+5, +15 or +24 V dc) and dc return is supplied through the 2 terminal logic supply connector, marked with + or –.
- Logic supply dc return is connected to all even pins of the 25 or 50 pin edge card connector
- Signal pin is pulled up to +Vcc when not asserted, down to dc return when asserted.
- The backplane is shipped with a jumper configuration to supply the logic voltage through pins 1 and 49 (1 and 25) of the edge connector.
- Logic-side connector pin numbers are for 50-pin connector. Pin numbers in ( ) are for 26-pin connector.
- 1781-A8A and 1771-JMB8 signal-side connections are via a 50 conductor edge connector. WRC4-A8H and 1771-JMB8H use a header connector.
The WRC4-A8H, 1771-JMB8, 1771-JMB8H and 1781-A8A mounting boards can be used with up to 8 WRC4, standard, miniature and 1781 slim modules respectively. The terminal blockaccepts only insulated wire with stripped ends. Each power side point is individually isolatedfrom each other. The signal side has a common logic supply bus (+Vcc and dc return) shared with each of the modules. Specify1781-CxEx Cable Assembly for 1771-JMB8 and 1781-A8A. Specify 1781-CxHx Cable Assembly for WRC4-A8H and 1771-JMB8(H). Specify WRC4-A8H-DIN and 1782-A8A for mounting on DIN rails such as WRC50022. 1771-JMB8 and 1771-JMB8H are not available for DIN mounting.