CT-TDR-512 Trigger Delay Relay Module – Adjustable Delay-Off Timer 0.1s–1hr, Optocoupler Isolated, DC 5V/12V, 10A SPDT

The CT-TDR-512 is a compact trigger-activated delay relay module that converts a momentary signal from any normally-open (NO) switch or sensor into a timed relay output. Trigger it with push buttons, touch switches, micro switches, reed switches, or vibration sensors — the onboard 10A SPDT relay holds the load for the set delay period, then releases automatically.

Built for machine and automation equipment retrofits, PLC industrial control, vibration alarm circuits, robotics, and smart product integration. A trigger pulse of just 1ms is sufficient to activate the timing cycle, and the module draws under 5mA at idle.

Key Features

• Optocoupler-isolated trigger input for strong anti-interference performance in electrically noisy industrial environments
• Precision timing chip for accurate, repeatable delay control
• 8 selectable time ranges from 0.1 seconds up to 1 hour via jumpers, with potentiometer fine adjustment (clockwise = longer delay)
• 100,000-cycle relay lifespan at maximum rated power
• Onboard PWR and TIME indicator LEDs for at-a-glance status

Specifications

Delay Time Range Selection

Set jumpers S1 and S2 to select the base range, add jumper S4 to multiply into the extended range, then fine-tune within the range using the onboard potentiometer (TIME-ADJ). Clockwise adjustment increases delay time:

Engineering note: for maximum service life, derate contact loading to approximately 50% of the rated capacity in continuous-duty applications.

Typical Applications

• Machine and automation equipment modification
• PLC industrial control circuits
• Vibration alarm sensing devices (pair with a NO vibration sensor)
• Robotics and intelligent product integration
• Timed lighting, fan, pump, and solenoid control from a momentary button

Frequently Asked Questions

How do I set the delay time?
Select a base range with jumpers S1 and S2, insert jumper S4 for the extended multiplier range, then dial in the exact delay with the TIME-ADJ potentiometer — clockwise increases the delay. The 8 ranges span 0.1 seconds up to 1 hour.

Is the trigger input isolated?
Yes. The trigger circuit is optocoupler-isolated from the timing and relay stages, giving strong anti-interference performance in industrial environments with motors, contactors, or long trigger wire runs.

What kind of switches can trigger this module?
Any normally-open, self-resetting switch or sensor: push buttons, touch switches, micro switches, reed switches, and vibration sensors. A pulse of 1 ms or longer starts the timing cycle.

Can it switch AC loads?
Yes. The onboard relay is rated 10A at 250VAC and 10A at 30VDC. For continuous-duty loads, we recommend derating to about 50% of rated capacity to extend relay life.

Does it work on both 5V and 12V systems?
Yes — the module supports DC 5V/12V supply. Verify your supply matches the marked input before wiring.

Is this suitable for PLC interfacing?
Yes. Its low trigger threshold, optocoupler-isolated input, and dry-contact relay output make it a common choice for PLC input conditioning and output expansion in industrial control panels.