Digital Countdown Timer (99 Minutes or 999.9 Seconds)

A simple to operate and useful countdown timer with digital display and relay output. The circuit is PIC based to ensure accuracy and reliability. It is ideal for use in automatic machines and in programmable time counting in general.

Simple 3-button operation (START / COUNT / RESET). Choice of counting down in 1 Second or 0.1 Second increments. Countdown time can be set up to either 99 Minutes 59 Seconds or 999.9 Seconds.

Relay actives when countdown commences and turns off again when zero is reached. On reaching zero the display returns to the previously programmed time for repeat operation or reprogramming as required.

Countdown can be paused and resumed using the Count and Start buttons respectively (relay turns off when timer is paused using this method). Alternatively, countdown can be paused by pressing and holding the Start button (relay remains on using this method).

Relay has both NO and NC contacts. Time scale is easily set using an onboard jumper. A battery backup connection point is provided so time setting is retained in event of power loss.

The unit consists of two PCBs, one for the control unit and the other for the display panel. Kit version includes solder for assembly.