Multi-Mode Universal Timer ( 12 Volts )

[petelai]

Dear All,

I am very new to electronics and I currently have a project which requires a switch to be activated for approx 6 seconds. This allows a motor to run for this set time and then stop. I have found many Multi-Mode Universal Timer kits which i can buy. However, the small motor i wish to activate with a timer is run of a 6volt powerpack battery so the unit is transportable but all of the kits i have seen require a 12 volt dc supply to operate. Is there any way I can get 12 volts from a 6 volt battery or can i just change some of the components in the kit or even better is there a 6-12volt converter kit available?

Here is a link to one of the kits i have been looking at.

**broken link removed**

Thanks in advance

Peter

 

[Torben]

Hi Peter! Welcome to the forum.

Usually it's a better idea to post *what* you're trying to do, instead of *how*. Often the more experienced members will have a simpler/better solution.

How much current do you need to switch? If all you need to do really is turn something on for 6 seconds and then off again, probably the easiest idea would be to use a 555 and a transistor or relay.

What will be the trigger--what signal will tell the thing when it's time to start the 6-second-on pulse?


Torben

 

[Boncuk]

Hi Peter,

also welcome to the forum.

I took a look at the user manual of the device. It is easy to modify it to work at 6V.

Omit the 7805 (included in the kit) and replace with an LM2940CT5, a low dropout voltage regulator. The relay must be replaced by a 6V type.

In the kit it is a 12V type and works at Uin minus the forward voltage drop of D1 (~11.3V at Uin=12V)

This is the only part requiring 12V.

Hope that helps.

Regards

Hans

 

[petelai]

Re:Timer

Hi,
Thanks to both of you for your quick replies. I actually bought the following timer

**broken link removed**

And i swapped the 12volt relay for a six volt version. It works fine using six volts. The problem I have is the potentiometer is very sensitive and it doesnt allow me to set the timer less then 10 seconds. I presume I can change this for a different size?

Thanks in advance

Peter