Technical data

ManualsBrandsAeca ManualsBattery ChargerXTH 3000-12

Hybrid Systems

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12/24/48 V DC

400 V AC

C C C C

A A

Key:

A Solar modules

B Solar charge controller Steca Power Tarom

C Battery

D 3 sine wave inverter Steca Xtender XTH

E Data logger Steca PA Tarcom

F Current sensor (Shunt) Steca PA HS200

G Electrical load (400 V AC)

H Remote control Steca PA 15

I Diesel generator

K Public grid/Wind energy

Three-phase hybrid systems

The control concept is similar to that of the single-

phase system. If more than one Steca Tarom / Power

Tarom is employed, one of the devices must be desig-

nated as the master Tarom. All other charge con-

trollers are then automatically designated as slave

Taroms. The master Tarom / Power Tarom is directly

connected to the battery and all slaves are connected

to the DC bus. Only the master Tarom / Power Tarom

shows the correct state of charge on its display and

controls the energy flow around the system. Slave

Taroms / Power Taroms perform the function of con-

trolling the charging from the connected PV modules.

In order to assemble a three-phase energy supply,

three inverters are connected to the DC bus. For this,

the inverters must be specially designed in order to

allow three-phase operation. Various three-phase

generators can be connected to the three inverters

for controlled recharging of the battery via a Steca

PA 15 and a relay. These may be wind, water, or die-

sel generators; or the public grid. Suitable inverters

with integrated battery chargers in three-phase mo-

de are the Steca Xtender devices, which can be em-

ployed from 12 V / 2 kW to 48 V / 24 kW per phase.

In total, a maximum of 72 kW can be supplied.

Both single-phase and three-phase hybrid system

concepts are based on the same principles of energy

management. With the help of the Steca PA HS200

current sensor, the charge and discharge currents of

the components, such as slave Taroms / Power Taroms,

inverters etc., are determined and communicated

to the master Tarom / Power Tarom. Based on the

calculated state of charge of the battery, the Steca

PA 15 switches the extra generator on or off. The

three single-phase inverters switch off if the voltage

falls below a given threshold in order to protect the

battery from deep discharge.

12/24/48 V DC 230 V AC

A A

C C C C

Single-phase hybrid systems

The central, intelligent element within the system is

the Steca Tarom or Power Tarom solar charge con-

troller: it controls the energy flow and protects the

battery against critical states. Steca Tarom/Power

Tarom is directly connected to the battery, just as the

DC bus is. Using a shunt, the Steca PA HS200, which

is situated on the minus cable attached to the batte-

ry, the battery current is measured and this informa-

tion is passed on to the Steca Tarom / Power Tarom.

Further components, such as an inverter or the Steca

PA 15 remote control, are directly connected to the

DC bus. In order to automatically start a diesel gene-

rator if the battery’s state of charge (SOC) falls below

an adjustable threshold, the output of the Steca PA

15 is connected to a relay.The normally open contact

of the relay switches the diesel generator on, and

subsequently switches it off again.

The Steca Tarom / Power Tarom controls the DC

hybrid system. The Steca PA HS200 current sensor

transfers all infor mation on the charge and dischar-

ge currents at the DC bus to the Steca Tarom / Pow-

er Tarom. With the aid of this data, the controller

is able to calculate the current state of charge of

the battery. This information is transferred via the

DC cabling (powerline modulation) to all connected

Steca PA 15. Every Steca PA 15 can be independent-

ly configured to a certain switch-on and switch-off

threshold of the state of charge.

If, in the above example, the inverter is discharging

the battery, then this information is transferred to

the Steca Tarom / Power Tarom, which calculates

the state of charge. As soon as the state of char-

ge falls below the appointed threshold value of the

connected Steca PA 15 (e.g. 30 %), the controller

switches on the diesel generator via a relay. The load

is now being supplied from the generator, and at the

same time the battery is being recharged. After the

state of charge has reached the Steca PA 15’s ap-

pointed upper value (e.g. 90 %), the diesel generator

is switched off again.

In order to create an automatic energy management

system, the AC output of the diesel generator is con-

nected to the AC input of the inverter (with integra-

ted battery charger). The load is always connected to

the output of the inverter. If the diesel generator is

running, and this current flows to the inverter, then

the inverter automatically switches to transfer mo-

de. The loads are supplied from the diesel generator

whilst the battery recharges via the inverter. If the

AC output voltage of the diesel generator falls un-

der a certain voltage level, which can be adjusted on

the inverter, then battery operation is automatically

switched back on.

This system allows for automatic energy manage-

ment which gets optimum use from the available

solar energy, maintains the batteries reliably, and en-

sures electricity supply around the clock.