Why you need a controller

The main function of a controller or regulator is to fully charge a battery without permitting overcharge. If a solar array is connected to lead acid batteries with no overcharge protection, battery life will be compromised. Simple controllers contain a relay that opens the charging circuit, terminating the charge at a pre-set high voltage and, once a pre-set low voltage is reached, closes the circuit, allowing charging to continue. More sophisticated controllers have several stages and...

Powerline Example System

12 io 48 modules typical 51 to 120 watts each Fixed or tracking, roof or ground mount for selected number and size module Module Interconnects Weatherproof conduit encasing wiring between modules Combiner enclosures for parallel connections at array Lightning protection - SOV in combiner box. Cable run from combiner box to powercenter total footage - out and back The system outlined here should serve as a guideline. The price will vary depending upon your requirements and the specific...

Recreational Vehicle Systems

Solar modules and RV's with batteries are a natural match. Since catteries are charged when traveling, RV's normally depend mostly on the vehicle's alternator for the primary power source. Power to charge the battery Dank is also provided through a converter when plugged into the utility. However, for those who like to spend days, weeks (or longer) not traveling and not plugged in, photovoltaics can mean freedom. And, because a PV array can put as much power into your batteries during an hour...

Solar Modules

The current and power output of photovoltaic modules are approximately proportional to sunlight intensity. At a given intensity, a module's output current and operating voltage are determined by the characteristics of the load. If that load is a battery, the battery's internal resistance will dictate the module's operating voltage. A module which is rated at 17 volts will put out less than its rated power when used in a battery system. This is because the working voltage will be between 12 and...

Batteries continued

Due to impurities in the chemicals used for battery construction, batteries will lose power to local action, an internal reaction which occurs whether we are using the battery or not. This slow discharging is termed self-discharge. Self-discharge rates vary greatly among battery types and varies with temperature. The rate also increases with the age of a battery, so much so that an old battery may require a significant amount of charging just to stay even. Even new batteries may lose 1 to 2 of...

CABIN Example System

100 to 500 Watt Array 12 Volts Nominal* AC and DC Loads Fixed Module Mount Stacking Vertical Configuration Roof Mounted Perfect for the energy conscious homeowner or vacation cabin. This system will provide a combination of 12 volt DC and 120 volt AC power without the noise and hassle of a generator. Enjoy the benefits of silent electricity such as music, lighting, pressurized delivered water - all at your perfect get-away spot. 830 watt hours daily from a 5 hour equivalent day. Batteries - 12...

Inverters with Builtin Battery Chargers

Many of today's inverters incorporate battery charging circuitry. This is easily and economically accomplished because of the design of most inverters. Inverters step up low voltage and change DC power to AC power. Battery chargers do the reverse of this. Additional circuitry is all that is required to add a whole second function and economically create an Inverter Charger. Transfer switches are also incorporated into these Inverter Chargers so that the AC loaas can be powered directly from the...

Multistage Battery Charging

Lead Acid Battery Hazard

A typical 12 volt lead-acid battery must be taken to approximately 14.2-14.4 VDC before it is fully charged. (For 24 volt systems double these figures.) If taken to a lesser voltage level, some of the sulfate deposits that form during discharge will remain on the plates. Over time, these deposits will cause a 200 amp-hour battery to act more like a 100 amp-hour battery, and battery life will be considerably shortened. Once fully charged, batteries should be held at a considerably lower voltage...

Generator Placement and Powersheds

Powersheds are a common outbuilding on the remote homestead. They often serve multiple functions of housing the generator, batteries and power conditioning equipment required with your PV system. Beyond this, they can also house tools and equipment as well as support the solar array if oiaced in a sunny, non-shaded area. It is a good idea to keep flammable fueis and gasses in a separate building rather than the building in which one sleeps. The sound insulation qualities of a powershed offer...

Used Batteries

Used lead acid batteries, especially large two volt telephone type cells can sometimes be found for sale. While used solar modules and inverters are usually an acceptable risK, used batteries are a high risk proposition. Should you consider them In our experience, it is difficult to know just how an older battery has been used. Has the previous user taken good care of the cells or have they been neglected7 Have they actually been load tested or just cleaned ud and recharged Our recommendation...

Battery Enclosures

Install your batteries in a warm, cry location. 55-80 degrees F. s the optimum temperature range lower or mgher than this and performance diminishes significantly. Because batteries produce a potentially explosive mixture of hyaro-gen and oxygen, venting is needed to orevent a buiiauD. 5ince hyarogen is lighter than air it has a tendency to rise, if venting is placed at tne top of the battery enclosure and air is Drought in from the bottom, this gas wiil move up and out of the battery area....

Batteries The Heart of the System

A Solar Electric system is made up of a number of components, ana of these, none needs as much attention as the batteries. Thouan the idea ana usage of a battery bank is very simple, if batteries are neglected, degradation can occur at a fast pace. As someone in the industry once put it, few batteries die a natural death, most are murdered. The following information is designed to tell you how to get the longest life possible from your battery bank. This is strictly flooded cell lead-acid...