MS121TB terminal board (for production use)

The MS121TB (shown mounted on an MS121B board) converts the plug-in I/O and power connections to screw terminals for easy wiring in low-volume production situations.

This unit will only work on the MS121B board, which has I/O pins at right angles to the main board. Earlier models, MS12 and MS121 (non-B) had their I/O pins parallel to the board.

Using the MS121TB

When you receive the MS121TB, the mounting hardware will be loose. You need to assemble it yourself. Use the picture above as a guide. You get the correct board to board spacing with one tubular spacer and a flat nylon washer (highlighted in the picture). The terminal board is permanently fixed to the controller.When plugging the two boards together, take care to align the connectors properly. It is perfectly normal for a small part of the pins on the controller to be visible when the two boards are connected.

External input and output devices are connected using the same principles as connecting directly to the controller board. The only difference is that the plug-in pins of the MS121 have been extended to screw terminals.