DCT101 Digital Countdown Timer – 12 VDC

The classic timer module that many still rely on – simple, tough and smart.

Remember this one?

Before touchscreen displays and multi-mode microcontrollers became standard,
Bolec’s DCT101 Digital Countdown Timer was the go-to solution for
timed engine shutdowns on irrigation pumps, generators and diesel power units.
It’s a simple design — yet after all these years, many of these little blue boxes are still running perfectly in the field.

Although our modern timers such as the BMT-55 and
TM301 offer greater precision and flexibility,
the DCT101 holds a special place in Bolec’s history as one of our most practical and durable early digital modules.

How it works

The DCT101 is a compact 12 V digital countdown timer with a two-digit LED display
and an on-panel toggle switch for easy operation. It was designed to automatically
turn off ignition power after a set number of hours — perfect for unattended irrigation engines
that need to stop after a watering cycle.

• Normal mode: Power flows straight through the relay contacts to ignition and gauges — timer inactive.
• Timer mode: The built-in relay holds the circuit on while counting down, then de-energises to shut the engine down.
• Display flashes a dot once per second to show countdown activity.
• Settable from 1 – 20 hours in whole-hour increments using simple ▲ / ▼ buttons.

When time expires, the relay cuts ignition and the display alternates between zeros,
drawing minimal current until reset.
Flicking the toggle back to “Normal” immediately cancels the timer and restores manual operation.

Simple wiring – three connections

• 🟠 Orange: +12 V (switched ignition supply)
• ⚫ Black: Ground
• ⚪ White: Relay N/O output to solenoid or ignition circuit

Installation was refreshingly straightforward — just three wires and a toggle switch.
The DCT101 could be mounted in a small box under the dash or near the control panel.

Why it was popular

What made the DCT101 stand out wasn’t fancy logic or data logging — it was
dependability. Farmers, mechanics and pump installers trusted it because:

• 🕒 Simple manual setup — no programming needed.
• ⚙️ Mechanical toggle switch for immediate control feedback.
• 🔋 Minimal current draw — safe to leave connected to battery for long periods.
• 🧱 Rugged design that survived heat, dust and moisture.

Today’s alternatives

Bolec continues to produce more advanced timer modules such as the
BMT-55 Multi-Mode Timer and
TM301 Delay Timer — both capable of adjustable delay,
repeat cycles and fine-tuned digital control.
But every so often, someone still calls asking for the original DCT101 — and yes,
we still make small runs for replacement and legacy applications.

Specifications

Still available

We keep limited stock of the DCT101 for customers with existing control panels and
vintage irrigation systems. If you’re servicing or restoring older units and need a direct drop-in replacement,
send us a message.

Bolec Electronics — Australian-made electronic modules for engine control and protection since 1983.