The HK1656 time relay is a ready-to-use enclosed device designed to control electrical loads using a negative -12 V trigger pulse. It operates as a pulse-activated timer with an adjustable ON time.
When power is applied, the timer remains in standby mode waiting for a trigger pulse. Upon receiving a negative -12 V pulse, the relay switches ON and remains active for the preset time. After the time expires, the relay switches OFF and returns to standby mode, waiting for a new trigger pulse.
If the trigger pulse lasts longer than the preset time, the relay switches OFF after the time expires and can be activated again only by a new pulse.
The ON time is smoothly adjustable from 1 to 30 units using a trimmer potentiometer. The time unit (seconds, minutes or hours) is selected via jumpers with the power OFF. LED indicators show power and relay status.

Technical Specifications:
Operating principle: negative pulse activated time relay (-12 V).
ON time: 1 - 30 seconds, minutes or hours.
Time range selection:
- W1 closed, W2 closed - seconds,
- W1 closed, W2 open - minutes,
- W1 open, W2 closed - hours.
Time adjustment: trimmer potentiometer.
Indication:
- power LED,
- relay ON LED.
Dimensions:
- PCB: 49 x 29 mm,
- Enclosure: 55 x 35 x 20 mm.
Relay output:
- Normally Open contact (NO),
- Common contact (COM),
- Normally Closed contact (NC).
Relay ratings:
- 15 A / 125 V DC,
- 15 A / 24 V DC or AC,
- 10 A / 250 V AC.
Supply voltage: 10 - 14 V DC.
Current consumption:
- relay OFF: 8 mA,
- relay ON: 48 mA.

This product is a boxed finished product.
It is also available as a fully assembled module (without box) - Product code 1606 (separate product).