AKG BP 4000 - Manual

Features

• Intelligent battery supply system

comprising CU 4000 charger and
BP 4000 battery pack

• Microprocessor controlled charge/

discharge monitoring function

• One-hour quick charging and Battery

Recovery Management

• Charging compartment allows battery

pack to be charged inside the
transmitter

CU

4000

/ BP

4000

Description

The AKG charging system 4000 consists of the

CU 4000 charging unit

and the

BP

4000 battery pack

. The charging unit itself is a stand-alone unit in a rugged plastic

housing, featuring

2

charging compartments, each mechanically designed to hold

either one HT 4000 handheld transmitter, a PT 4000 bodypack transmitter or a BP
4000 spare battery pack.
Two battery packs can be charged simultaneously by the CU 4000, if the battery
pack is installed in either the HT 4000 or PT 4000 transmitters. There is no need
to remove the battery pack from the transmitters since these transmitters are equipped
with on- board charging contacts for a

plug-in charge

.

The

sophisticated charging electronics

of the CU 4000 comprises revolutionary

functions to

carefully charge and service the

BP 4000

battery packs

over the full

lifetime of the battery.

The basic charging function is based on a

trickle charge

system with so-called

inflection

point

switch-off automation. Safety switch off occurs by detection of the peak voltage,

the negative voltage slope or a predetermined time out. Thus the battery pack is
prevented

from overcharging

. An integrated

two-slot power management

system allows

the Charging unit to charge two battery packs simultaneously in
approximately 1 hour.
Since the BP 4000 battery pack incorporates

micro-

processor-controlled surveillance intelligence

, there

is a permanent data stream between the Charging
Unit and the Battery Pack to protect the batteries
from any damage caused by the charging process.
A

charge balance management

circuit controls the

exact amount of energy to be charged in the pack
as the amount that was taken out of the pack (2nd
level overcharge protection). The charge balance
management also features a

self-discharging counter

used to detect the exact battery pack status after a
long period of storage. With the help of this charge
balance management, an accurate

remaining battery life

display

can be realized on the transmitters (transferred via pilot

tone to the SR 4000 receiver).
All necessary battery pack data will be stored in the

internal RAM or EPROM-

memory

of the pack. All predetermined and initial parameters are stored in EPROM-

memory of the battery pack to perform a correct recovery cycle.
The battery pack also features an

internal temperature surveillance circuit

that adjusts

the charging current of the CU4000 to protect the device in case of low or high
temperature during loading.

To reduce the so-called memory effect which leads to decreasing battery capacity,
the communication between the BP 4000 and the CU 4000 is able to calculate if
the batteries need a

recovery cycle

by the help of the stored date in the BP 4000.

In this case, the CU 4000 draws the user’s attention to this possible problem and
suggests starting a recovery cycle. The user can activate the recovery cycle via a
recovery button on the CU 4000´s front panel. The recovery cycle refreshes the battery
pack by charging and discharging cycles to determine the actual capacity and initialize
the capacity counter for accurate use time calculation.
Other controls include a

3-step LED display

showing the charging status. A

lockable

DC connector

on the rear panel of the CU allows the unit to be powered by either an

external DC adapter or by the optional

PSU 4000

central power supply.

Due to the sophisticated charging system, the battery pack can power the HT 4000
and PT 4000 for

up to 12 hours

with one full charging cycle, plus its gentle charging

function will ensure up

to 1,000 charging cycles

.