12 Volt Programmable Timer Switch
12 Volt Programmable Timer Switch
Automatically control devices with a 12 Volt powered timer switch
electronics | lighting | generalAutomatic
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.
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
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
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
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.
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 2008Comment 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 4060BBuild a reliable timer to switch devices on and off - from 30 seconds to 24 hours
Article Last Modified: 09:58, 15th Aug 2009electronics | electric circuitRepeat Timer CircuitMake a repeat timer circuit with large intervals between ON times
Article Last Modified: 09:58, 15th Aug 2009electric circuit | electronics | generalConvert Digital Mains Timer To Low VoltageConvert a cheap digital mains timer into a low voltage programmable timer relay
Article Last Modified: 10:21, 15th Nov 2008electronics | electric circuit | generalUse Thermostat as 12 Volt TimerFind out how an old battery powered thermostat can be used as a low voltage automatic timer
Article Last Modified: 13:21, 7th Aug 2008electric circuit | electronics | generalConvert Thermostat to 12v Timer SwitchFind out how to modify a battery powered thermostat to be used as a 12 Volt DC timer switch
Article Last Modified: 16:12, 24th Mar 2009electronics | electric circuit | generalWireless Electricity MonitorsUp to date details of the wireless electricity monitors for sale in the UK
Article Last Modified: 13:51, 19th Mar 2010shopping | energy efficiency | carbonLED Dimmer CircuitFind out how to put together a simple but efficient PWM dimmer circuit for LEDs
Article Last Modified: 16:03, 21st Nov 2007lighting | electronics | electric circuitUsing The LM317T With LED LightingUse an LM317T to regulate the current in LED lighting projects
Article Last Modified: 12:47, 12th Mar 2008lighting | electric circuitAutomatic Hen House Door Closer OpenerFind out how to put together a DIY automatic hen house door opener and closer
Article Last Modified: 11:47, 27th Jun 2009electric circuit | general | solarSolar Battery Charger With LM317TFind out how to make a current controlled solar battery charger using an LM317T
Article Last Modified: 09:34, 30th Mar 2007solar | education | electric circuit
|
|
|
