D+7A Hardwired Connections & Process Control

[J Slade]

Greetings!

Over the years I've seen installations where these vintage cards & systems were used for process control, but never the hardwired connections.

Just wondering if anyone in the group was involved with connecting the D+7A to the real world back in the day for process control applications.  I'll be wiring mine up in the near future and I'd like to replicate the best / typical practices from back in the day ...

Thanks.

[J Slade]

Considering how delicate soldered ribbon cable connections can be, I've been wondering what direction to go with taking all D+7A signal lines (44 pins) out of an S100 chassis to an external terminal block.

Signals:

- Digital inputs

- Digital outputs

- Analog inputs

- Analog outputs

- Related grounds

- strobes

- Voltage supplies

Potential paths forward:  

- 44 pin edge card connector soldered to 4 separate multi-conductor round cables to external terminal blocks

- 44 pin edge card connector soldered to custom PCB with 50 pin IDC header / 1 IDC cable / 1 breakout terminal board like this:

It seems putting all 44 of the signals on one ribbon cable might not be the best idea.

- 44 pin edge card connector soldered to custom PCB with 2 x 26 pin IDC connectors / 2 IDC cables / 1 breakout terminal board like this:

- 44 pin edge card connector soldered to custom PCB with 4 x 12 pin IDC connectors / 4 IDC cables / 2 breakout terminal boards like these:

- some other approach?

The IDC/TB approach will make this a hard wired solution.  To change what's hanging off the end of the TBs will require changing the wiring.

Alternatively, I was wondering about cutting prefab cables in half:

- 2 DA-15 (4 cables in all with 1 for each signal type), or;

- 1 DB-25 (2 cables in all with 1 for analog / 1 for digital).

These cables would then be soldered to the 44 pin connector and the D-sub connectors could be plugged into whatever has been wired up.

Using this approach, it would be very easy to change what the D+7A board was connected to (switch box with lights, meters, etc) or an Arduino with A/D I/O.

Any thoughts or ideas on what you think would produce best outcome would be greatly appreciated.

Many thanks.