Electrical Light Circuit Diagram - Seven Segment Counter Display Circuit Description. Here is the circuit diagram of a seven segment counter based on the counter IC CD 4033. This circuit can be used in conjunction with various circuits where a counter to display the progress adds some more attraction.. HOW TO USE THE CIRCUIT DIAGRAMS All of the information in this folder is intended for use with the Electrical Reference Library booklet. The circuit diagrams are presented with Power and Ground. In the detailed design phase, the electrical designer must size and select the wires/cables, conduits, starters, disconnects and switchgear necessary for supplying power and control to HVAC equipment..