A way of automatically switching a switch at a certain time of day?

Hi all,

I just wondered if anyone knows of a simple (and accurate) way of turning a relay on/off and preset times of the day. I'd rather not use a PLC to try and keep the expense down (ideally). I wondered if there was a 'time of day' relay or something that someone has come across?

We have a keyswitch at the moment that switches on the main power to one of the production halls. This gets turned off on Friday night and then security are meant to turn it on in the morning at 6am on Saturday and Sunday for the weekend shift. They sometimes forget and so I would ideally like to have some way of automatically mimicking the key switch at 6am on Saturday and Sunday.

Does anyone know the best way of achieving this? Anyone seen anything like this before?

Many thanks for any help you can give me.

Cheers

;-)

They are used all the time for things like turning on/off heating/cooling equipment and lighting for places that are occupied/unoccupied at varying times of the month, year, day, etc. Like a programmable thremostat in your house.

We always called them time clocks. They come in varying degrees of complexity. Some can keep track of holiday shutdowns, daylight savings, etc. Some simple ones are merely a rotating disc with adjustable tabs that turn on/off the switch as they pass the switch location.

Tharon

thanks for the info. I've found a device exactly as you describe by searching for 'time clock relay' on google. Just need to dig about now and find the right one for the job.

Thanks again for the info.

Cheers

;-)

For anyone else looking for a similar item then this is what I've decided to get:
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=3970542#header

Thanks again Tharon ;-)

A PICO or the like is very reasonable.

Tom, thanks for the info. Will have a look into it.

;-)