9Pcs NE555 DC 12V Delay Timer Relay Switch Module Adjustable Module 0 to 10 Second Converter Timer

While 4 didn't work at all, the 6 that did worked great in my cars to delay turn on of devices like dash cameras, that would sometime hang due to low voltage during cranking. Now all devices are delayed about 7 seconds and always work.

I was very pleased with the quality of manufacture. Soldering of components was cleanly done.All of them checked out perfectly. Hooking them up was straight-forward to anyone with a basic electronic background, even without instructions.I also was very impressed that even though the board ran on 12 VDC, the relay contacts could handle up to 10 amps @ 240 VAC.

I used the timer in a Halloween animation project - using an IR interrupter to trigger lights and a "home depot" animatronic. Both require contact closure to activate. Light need to stay on for the duration of the program. The animatronic must not be retriggered during the program. Components all purchase from Amazon - 12V battery, programmable timer relay, SPST 12v relays, toggle switch, screw terminal strip, and, in fact wire and soldering iron! The Delay module has no trigger input. It just has power and ground (+ and -). When applied, there is a delay on the order of seconds, which is supposed to be adjustable. After the delay, a relay is triggered to an ON state. The relay provides Normally Open and Normally Closed outputs. To adjust the delay, there is a potentiometer on the board. A counter clockwise turn reduces the delay (if the module is healthy - the first one I tried delays for 10 seconds no matter how much I turn the "pot". My application used this device to create a brief contact closure to trigger the animatronic, and not allow it to be retriggered during its "program". Issues with module: no documentation. Incoherent instructions in Amazon listing. Poor quality control. No trigger.

seems to work as advertised. Solderpoints on relay were not good and required re-soldering

I used this to make a quick reduced voltage hold-in circuit for a water solenoid. It’s been working perfectly for months.

Very stable voltage control

This unit does exactly what I needed. You can adjust a delay time. After power is turned on. the unit will delay for the set period and then turn on the relay. The relay remains on until power is turned off. Unfortunately, when I installed one into my project, it failed within minutes. I assume the 555 IC failed. Another reviewer elsewhere indicated that the issue may be EMI noise due to a single power source. But I have no idea why mine failed. I have burned through 6 units.

it was just what my project needed