| REUK Shop | REUK Blog | Directory | About Us  |  | RSS Web Feed for Renewable Energy UK 

12 Volt Programmable Timer Switch



12 Volt Programmable Timer Switch

Automatically control devices with a 12 Volt powered timer switch

electronics | lighting | general
  Printer Friendly Version Print Article     

Automatic 24 hour timer switches for 240 Volt mains electricity are very easy to find and are very cheap - prices start at just 99 pence! With such a timer (see image below) it is possible to set the times a plugged in device (typically a lamp - but also fans, pumps, irrigation systems, and other appliances) will switch on and off through a 12- or 24-hour period.

240VAC Programmable Timer Switch

Unfortunately equivalent programmable timers for 12 Volt applications are not so easy to come by, and those that are available tend to be very expensive since they are not so mass produced. In this article we will introduce a couple of the better 12 Volt Timers available as well as looking into how you can make your own timer.

Flexcharge 8-Event Programmable 12 Volt Timer

Digital 12 Volt Programmable Timer Switch

Pictured above is a digital 12 Volt programmable timer manufactured in the USA by Flexcharge. Costing around US$85, this is a 7-day timer which can be programmed with up to 8 on (and 8 off) events per 12 hour period. An internal battery is included which will stored programming data for up to 3 months without external power.

DT-01 Digital 12 Volt Timer


DT-01 12 Volt DC Timer

Pictured above is the DT-01 Digital 12 Volt Programmable Timer - available in USA for around US$65. Typically used in automatic fish feeders (see super-feed.com for details), this timer provides up to 8 on and off cycles per day individually settable for the seven days of the week.

The internal lithium battery will retain programmed timings for up to five years when disconnected from the main 12 Volt battery, and the incorporated relay is rated at up to 16 Amps meaning this timer can be used to switch on and off up to 200 Watts of devices.

90-124uA are drawn by the timer when it is switched off (i.e. just 90 one-millionths of an Amp), and 33-49mA (i.e. 33 one-thousands of an Amp) when the relay is energized.

Click here for the DT-01 Specification Sheet.

Use a Programmable Thermostat as a Timer


Programmable thermostat used as a 12V timer

An affordable alternative to the dedicated 12 Volt timer discussed above is a programmable thermostat. These battery-powered devices can easily be converted to run from solar power, or from the battery bank of a renewable system (via a voltage regulator).

These thermostats contain a built-in relay which can be used to switch 12V DC and 240V AC devices on/off according to the times programmed in by the user. Used good quality units are available for as little as £10.00, and new Chinese imports start at around the same price.

Click here to read our Use Thermostat as 12 Volt Timer article.

Convert a Mains Powered Digital Programmable Timer

NEW - Click here to read our new article Convert Digital Mains Timer to Low Voltage to find out how to make a cheap low voltage digital programmable timer.

Make a 12 Volt 24 Hour Timer Circuit

Since commercial 12-Volt powered timers are so expensive, it is worth investigating putting one together yourself using easy to obtain electronic components.

Timer Circuit

Find out how to construct your own adjustable 24 Hour Timer using a 4060B binary counter chip by clicking here.



Article Last Modified: 13:26, 7th Aug 2008

Comment on this Article

If you have any comments on this article, please email them to neil@reuk.co.uk.


Recommended Related Articles

People who read this article also enjoyed the following articles:

Timer Circuits With 4060B
Build a reliable timer to switch devices on and off - from 30 seconds to 24 hours
Article Last Modified: 09:58, 15th Aug 2009
electronics | electric circuit

Use Thermostat as 12 Volt Timer
Find out how an old battery powered thermostat can be used as a low voltage automatic timer
Article Last Modified: 13:21, 7th Aug 2008
electric circuit | electronics | general

Repeat Timer Circuit
Make a repeat timer circuit with large intervals between ON times
Article Last Modified: 09:58, 15th Aug 2009
electric circuit | electronics | general

Make a Mini Wind Turbine Battery Charger
Convert a PC fan into a wind turbine battery charger
Article Last Modified: 20:19, 7th Aug 2012
wind | electronics | education

Convert Digital Mains Timer To Low Voltage
Convert a cheap digital mains timer into a low voltage programmable timer relay
Article Last Modified: 10:21, 15th Nov 2008
electronics | electric circuit | general

New Simple Hen House Door Controller
Details of our new 2013 simple design for an automatic hen house door controller
Article Last Modified: 11:45, 20th Apr 2013
electric circuit | general | solar

Automatic Hen House Door Closer Opener
Find out how to put together a DIY automatic hen house door opener and closer
Article Last Modified: 11:40, 20th Apr 2013
electric circuit | general | solar

Simple Elapsed Time Timer
Make a very simple and cheap automatic time elapsed timer with optional alarm
Article Last Modified: 13:38, 22nd Dec 2012
electronics | education

Solar Water Heating Swimming Pools
Build a solar powered water heating system for a swimming pool
Article Last Modified: 10:06, 8th Oct 2012
solar | water | heating

Heat Pump Tumble Dryer
Reduce power consumption with the latest heat pump tumble dryer technology
Article Last Modified: 20:16, 3rd Jan 2013
energy efficiency | general | shopping

© 2006-2013 REUK - All Rights Reserved
Page Last Updated on 25th May 2013 at 12:23:03pm

Recent
Blog Posts


1.Reducing Reflectivity of PV Solar Panels to Increase Efficiency

2.Low Voltage Disconnect with Display and Datalogger

3.Saudi Solar Power Boom About to Begin

4.Compressed Air for Storage of Renewable Energy

5.Offer of the Day – 80W Monocrystalline Solar Panel £71.98

6.Project of the Day – Wind Turbine Dynamic Blade Pitch Controller

7.Morocco Starts Vast Solar Energy Project

8.Follow Up to RC Helicopter Lighting Controller

9.Low Voltage Disconnect – User Programmable Set Points in Binary

10.UK Home Energy Smart Meter Project Delayed


Latest
Articles


New Simple Hen House Door Controller
Details of our new 2013 simple design for an automatic hen house door controller
electric circuit
11:45, 20th Apr 2013

Automatic Hen House Door Closer Opener
Find out how to put together a DIY automatic hen house door opener and closer
electric circuit
11:40, 20th Apr 2013

Butanol vs Ethanol Fuel of the Future
A brief introduction to Butanol/Biobutanol as an alternative to Ethanol
biomass
11:55, 19th Apr 2013

Cheap Pyroelectric Infrared PIR Detector
Details of a very affordable and flexible PIR motion detector
electronics
20:33, 16th Jan 2013

Heat Pump Tumble Dryer
Reduce power consumption with the latest heat pump tumble dryer technology
energy efficiency
20:16, 3rd Jan 2013

LED Spotlights
Find out about Energy Efficient LED spotlights
lighting
15:17, 3rd Jan 2013

Dimmable Energy Saving Lightbulbs
Find out more about low energy light bulbs which can be used with standard dimmer switches
lighting
14:36, 3rd Jan 2013

Review of Megaman Energy Saving Lightbulbs
Find out more about the Megaman range of CFL energy saving lightbulbs
lighting
14:08, 3rd Jan 2013



REUK Shop

Popular Items


REUK SUPER LDR DUSK DAWN RELAY CONTROLLER
Multi-function light detector triggered light/dark dawn/dusk relay controller
£19.95 each.
Complete Circuits



KARASOULI SCC 20 CHARGE CONTROLLER
20A rated wind turbine charge controller and dump load controller with blocking diode and heatsink
£43.95 each.
Renewable Energy System Parts



2013 SOLAR PUMP CONTROLLER WITH RELAY
New solar water heating pump controller with fitted 10A relay
£25.99 each.
Complete Circuits



REUK SUPER POULTRY LIGHTING CONTROLLER
Control up to 8 Watts of LED spotlights to stimulate egg production in birds
£29.99 each.
Complete Circuits



REUK SUPER TIMER 2
User programmable 12VDC powered 16A rated repeating relay timer. 1 second to 99 hours ON and OFF times
£23.99 each.
Complete Circuits



300 WATT POWER INVERTER
Convert 12V DC battery power into 230 AC to power portable televisions, computers, video recorders etc. 300 Watt power rating - peak power 600 Watts
£29.99 each.
Renewable Energy System Parts



CONVERTED PROGRAMMABLE DIGITAL TIMER RELAY
Mains powered programmable timer converted to low voltage with relay board
£21.99 each.
Renewable Energy System Parts



12 VOLT REGULATOR
Supply a fixed 12.0 Volt DC to your devices (up to 0.7 Amp output)
£4.79 each.
Complete Circuits



MR16 CERAMIC BULB HOLDER
Bulb holder for 12 Volt LED spotlight bulbs
£1.39 each.
Energy Efficient Lighting