Our Homeowner’s Association (HOA) wanted some lights at our beach area that members could easily turn on at night, but which would automatically go off after a couple of hours. I put together this project with three timers and some pushbuttons from AutomationDirect

that solves the problem nicely.

The timers have dials on the front, and can be adjusted from .05 seconds, up to 60 hours. We decided on 2 hours for our application…

How it works…

Users simply push the appropriate button to turn the lights on.
The lights automatically turn off after 2 hours (duration is selectable).
The reset button allows users to turn-off all the lights on demand.

Inside the cabinet

Here is a photo of the inside of the cabinet. The cabinet was already in place, and houses the breaker box, and some other electrical items. This small sub-panel was added to house the timers and terminal blocks. I had the miscellaneous parts, terminal blocks, din rail and wire duct, so all we have to buy were the pushbuttons and timers.

The terminal block at the top are just for power distribution, the blocks to the right of the timers are the outgoing “timed” power to the lights.

The Purchased Parts

Here’s the timer I used: MS4M-AP-ADC ($42)

This timer requires a socket, I used this one for DIN rail mounting ($6). A panel mount version is also available.

I also purchased these 30mm pushbuttons, each one comes with one set of normally open contacts:
HT8AAGA Green ($16.75)
HT8AAHA Black ($17.25)

AutomationdDirect sells smaller pushbuttons (22mm) for an even lower price, but I wanted these big, industrial buttons that can stand-up to years of use (and abuse).

I ordered the parts from AutomationDirect, and they shipped the same day

Timing Diagram

The MS4SM timer has four modes, I’m using the SF mode, or “signal off-delay”. This mode times from the falling edge of the button press, and allows the user to press the button again during the time-out to extend the time. For example, a user can press the button and start the timer, and then after one hour, before the lights have gone off, they can press the button again and extend the time. Other modes include: on-delay, flicker, and one-shot.

The dial on the front of the timer allows easy adjustment of the time period. The selectable ranges for the dial include: 0.05-0.6s, 0.1-1.2s, 0.25-3s, 0.5-6s, 1-12s, 2.5-30s, 5-60s, 0.5-6min, 1-12min, 2.5-30min, 5-60min, 0.5-6h, 1-12h, 2.5-30h, & 5-60h. I’m using the 0.5 – 6 hour range, and I have the dial set to 2, for 2 hours of time. It’s very easy to adjust.

Schematic

Here’s the schematic. I’ve wired 120VAC across terminals 2 and 10 to power the timers. The green pushbutton is wired across 2 and 6, and the black button is wired across 2 and 7. The lights themselves are wired across 1 and 3 (or you could use 11 and 9). For more current capacity you could wire across both of the normally open outputs.

The output contacts are rated: 5A at 30VDC resistive load, 1A @ 30VDC inductive load, 5A @ 250VAC resistive load, 2.5A @ 120VAC inductive load.

Here’s a link to the online manual for the timer.

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