Blog - Inverters DC/AC

Making your own island power system is not difficult. It is necessary to fit all the components together properly within manufacturers specification. We have divided this issue into three basic tasks:

First task it so fit the solar regulator and solar panel

MPPT solar regulator 12/24V tracer 10a, input 100v (TR-1210rn) is very suitable for single 240Wp solar panel by the maximum input power capability.

Maximum input power of TR-1210rn is 260W if 24V battery is used. This almost matches maximum power of selected Schutten 240Wp panel, which is 240W peak. Selected regulator and solar panel are perfect match. 

For areas with not so perfect solar conditions it is possible to connect more solar panels. Both serial and parallel connection is possible. Please see attached schema.

If 240Wp panel in not ideal conditions supplies for example 60W under normal sunlight, it is possible to connect more panels in parallel. Maximum PV power 260W / 60 = 4 solar panels in parallel

Solar Tracer regulator TR-1210rn allows input up to 100V.
Open circuit voltage of selected Schutten 240Wp panel is 29.9V. 100 / 29.9 = 3 solar panels in series

Both options are possible, but serial connection is always more advantageous with respect to lower currents in the circuit!

In case of sudden very good solar conditions and over exceeding allowed PV current or voltage of TR-1210rn solar tracer there is no danger of damage of the components because of integrated fail-safe features.

Our second task is to fir matching battery for our solar system:

For maximum power of TR-1210rn solar regulator 260W it is necessary to use 24V battery pack. It however depends on client’s requirements how much Ah capacity battery is suitable. For this example case let’s consider following requirements:

Every evening I need to power 3 LED bulbs 4W, laptop computer 40W, LCD TV 220W for 4 hours, plus I want have enough power to occasionally power shaving machine, bad lamp, charge phone, etc.

3x4 + 40 + 220=272W
272W x 4 hours = 1088Wh battery pack is needed

1088Wh/24V pack voltage = 45 Ah battery capacity is needed without reserve.
Suitable then might be the 60Ah battery pack 

CALB CA60FI LiFePO4 cells might be suitable option, as well as single LiFePo4 cells from other manufactures. In serial connection of 8 cells you can build a battery pack with help of connection material – copper terminal connections and stainless steel screws with washers and spring washers to secure proper current transfer.

LiFePo4 batteries needs protection from overcharge and overdischarge!No matter if the overcharge protection is secured by the solar regulator and ovedischarge protection by the 230V inverter, you must protect LiFePo4 battery further for case of failure of any of the components.

Suitable protection for 24V pack is BMS system, such as BMS123.

Third task is to choose suitable 230V DC/AC invertor. In GWL Power offer we do have only powerful 230V inverters suitable for much bigger solar systems. Fortunately 24VDC to 230VAC inverters became widely available accessory for Automotive (Truck and Camping) application.
For our example case we have considered required maximum power 272W continuous without reserves. For enough reserve it is optimal to choose 350W to 450W continuous power inverters (at least 20% more).

List of mentioned products:

• 1 pc of Schutten solar panels 240 Wp
• 1 pcs of GWL/Power MPPT Solar Regulator 12/24 V, Tracer 10 A, Input 100V (TR-1210RN)
• 8 pcs of GWL/Power CALB CA60FI - Lithium Cell LiFePO4 (3.2V/60Ah)
• 7 pcs of GWL/Power Terminal Connectors for LYP60AH
• 1 pc of GWL/Power BMS123 OFFGRID - Main Controller
• 6 pcs of GWL/Power BMS123 - Cell Module
• 1 pc of GWL/Power BMS123 - Cell Module IN
• 1 pc of GWL/Power BMS123 - Cell Module OUT
• Suitable 24VDC to 230AC controller

The installation is very easy. Just connect Solar regulator with Shutten solar panel with supplied wires. For connecting the battery and the load with solar regulator you will need your own cables and possibly also connectors for them for simple connecting to battery terminals. Please see attached instalation schema.

Connection of BMS123 system is little bit more complex, but let your mind be eased by the fact that BMS123 is one of the most simple BMS system on the market to both connect, configure and operate. Please see BMS123 schema.

More information, support and other options:

Where to get more information and pricing of the products:

http://www.ev-power.eu/BMS123-System/
http://www.ev-power.eu/Solar-GridFree/
http://www.ev-power.eu/Solar-Panels/
http://www.ev-power.eu/CALB-40Ah-400Ah/
http://www.ev-power.eu/CALB-terminals/

The support pages related to the issue:

http://gwl-power.tumblr.com/tagged/EnergyStorage
http://gwl-power.tumblr.com/tagged/solar
http://gwl-power.tumblr.com/tagged/Offgrid