The D1700 digital input output provide computer monitoring and control of industrial on/off signals. The modules provide fifteen I/O bits for sensing contact closures and controlling relays or annunciators. Two different pairs of modules are available in the D1700 series.
The D1701 and D1702 modules contain seven discrete digital inputs and eight open-collector digital outputs. The discrete input bits contain internal pull-up resistors allowing for direct connection of switches or contacts without the need for external components. The open-collector outputs can be used to control solid-state relays or annunciators. The outputs can be pulled up to +30Vdc and drive 30mA loads without damage. Refer to the D1000 documents for more information.
The D1711 and D1712 modules contain fifteen discrete digital I/O bits. Each bit is user selectable as either a digital input or digital output. Each input bit can monitor digital signals between 0-30Vdc with switching levels <+1Vdc = logic “0”, >+3.5Vdc = logic “1”. The outputs can be pulled up to +30Vdc and drive 100mA loads without damage. Refer to the D1700 documents for more information.
Enhanced features of the D1711 and D1712 include a communications watchdog timer, user-programmable starting value for each digital output bit and a continuous peer-to-peer configuration using two modules. The peer-to-peer mode allows two modules to communicate digital input status from one location to another. A digital input module can communicate its input status to a digital output module that will automatically reproduce the status levels on its digital outputs.
Each module contains either an RS-232 or RS-485 interface for direct connection to a host supervisory computer.