When you have a 12-Volt system and you need a timer to control your loads, the Flexcharge 12 VDC Programable Timer is your best option. The digital timer keeps track of the day of the week as well the time in minutes. With so much accuracy it virtually can turn on and off any load.
It is important to note that the Flexcharge timer can control 120 VAC loads; however, the timer needs to be powered by a 12 VDC circuit. The timer includes a rechargeable battery to keep the time when the power source is off.
It can only control one load at the time and it allows you to program 8 events for that load.
The Flexcharge digital timer is a 7-day, 8-event digital clock based programmable load controller. Eight ON and eight OFF events can be programmed independently, each with its own unique timing pattern.
It includes a replaceable internal battery which maintains the clock and programmed memory in the event of a system power failure for up to 3 months. Consumes less then 3mA in standby mode.
The internal DPST (double-pole-single-throw) relay switch can turn one load on at the same time that it turns another load off. The timer switch can handle up to 8 amps of inductive load or up to 16 amps of resistive load, at 6 to 36VDC or 120VAC. The timer requires 12V DC or AC to operate. It is reverse polarity protected. The manual override allows the user to turn the load ON or OFF as desired. Easy to use terminal block for wiring; dry contacts.
Example of use: use one ON event to have a light come on at 7 pm every day then use seven OFF events to turn the light off at a different time each day.
Quick guide for selecting the right charge controller
Each time you charge deep cycle batteries with solar panels, it's necessary to use a charge controller in the circuit to protect the battery from over charging, and in some instances from over discharging. The only exception is when using solar panels smaller than 5W. Choosing the most suitable charge controller is simple and only requires two steps:
Step 1 - Voltage selection
Select a charge controller that is compatible with the system voltage. The standard configurations are 12, 24, and 48 volts. If you are wiring your batteries for 24 volts you need a charge controller that is rated at 24 volts.
Some controllers are voltage specific, meaning that the voltage cannot be changed or substituted. Other more sophisticated controllers include a voltage auto-detect feature, which allows it to be used with different voltage settings.
Step 2 - Current capacity
Select a charge controller that can handle the maximum output current of the solar panel (or solar array). The maximum possible current that a PV panel can generate is the “short circuit current,” indicated as Isc in the panel’s label or specs sheet.
It’s recommended to include a safety factor for isolated events as well. For example, a solar panel with a Isc of 7.89 amp could potentially produce an extra 25% on a sunny day with very clear snow pack. (additional light reflected off the snow). This results in a possible maximum of 9.86 amp (7.89 x 1.25 = 9.86 amp). In this case, a 10 amp charge controller would be recommended.
Below you will find a quick guide to choosing the proper charge controller for several popular solar panel sizes.
12V olar panels 5W - 45W
Phocos CM 04 Charge Controller 4A, 12V
12V solar panels up to 70W
Flexcharge PV7D Charge Controller 7A - 12V