Specifications

129Contents, specifications and availability are subject to change serving the technical improvement.128 Contents, specifications and availability are subject to change serving the technical improvement.
13.0 V
13.8 V
14.4 V
1
5.0 V
0501- 302010 040
End-of-charging voltage
F
loat charging voltage
Time (t)
A temperature sensor is recommended when battery charging takes place in
varying or extreme ambient temperatures. This is because the optimal charging
voltage for a battery largely depends on the temperature conditions. In cold bat-
teries, for instance, the gas development voltage is higher than in warm batteries.
The sensor is fitted on the battery or close to it and measures the temperature.
Depending on the result, the battery charger adjusts the main charging and float
charging voltage. At high temperatures the voltage is reduced to prevent battery
gassing. At low temperatures the voltage is increased to improve the battery
charge. The diagram shows how the temperature sensor adjusts the charging
voltage to the temperature of the battery.
All PerfectCharge IU0U charges of series IU 1512 to IU 4512 can be equipped with
the TF-500 temperature sensor, which is available as optional extra (p. 135).
The advantages of a temperature sensor
U
(V)
I (A)
I
phase
U
phase
U
0 phase
Time (t)
I
10 %
I 80 %
l
imited at 4 or 8 h
I
U
To prevent overcharging when power is drawn from the battery while charging, the
duration of the U0 phase is limited.
Ideally, the system should switch from the main charging voltage U0 to the float
charging voltage U when the battery is 100% charged. A good indication for a fully
charged battery is a low current intake.
If an electrical appliance exerts a current load on the battery during the charging
phase (e.g. when a light is on), the charging current will never reach the low
current value required by the system to switch over to the U phase. As the U0 phase
is limited to a finite time, the switch-over to the U phase occurs regardless of the
charging voltage level. This makes it impossible to overcharge the battery.
Limited time of the U0 phase
Temperature compensation
When two or more batteries are used independent of one another, the load on
them will be different and so will the required extent of recharging.
This is taken into account by the PerfectCharge double and triple chargers in series
IU 1512 to IU 4512 (p. 132 – 135). These units feature two or three battery outputs.
Some of them have an extra output for charging the starter battery (p. 133/134).
The chargers incorporate diodes to divide the charging current and prevent charge
compensation between the batteries. While charging the weaker battery is initially
brought to the charge of the stronger one. Both (or all three) batteries are then
charged at the same voltage level until the full charge is reached. Naturally, it is
also possible to connect just one or two batteries to a double or triple charger.
Simultaneous charging of several batteries
IU0U chargers
Intelligent and powerful
U (V)
I (A)
I phase U phaseU0 phase
Time (t)
I 10 %
I 80 %
limited at 4 or 8 h
I
U
This fast and gentle charging technology represents an extension of the
well-proven IU charging curve.
It includes the additional time constant 0 and a further constant voltage U for
compensation charging. Like with IU charging characteristics charging is initially
performed with a constant current. When the gas development voltage has been
reached, the voltage is maintained at the same level until the charging current has
fallen to a minimum. At that point the charging voltage is reduced to the float
charging level – the charging process is completed.
IU0U charging characteristics
Battery chargers used in campervans or boats are facing a tough job. They have to recharge the leisure batteries as quickly and fully as
possible. At the same time, battery power is drawn from the battery for lighting and other electrical appliances.
WAECO IU0U automatic chargers are able to meet these requirements for one significant reason: the limited time of the main charging phase.
They are available in various performance categories, from 2 A to 45 A.
How powerful a battery charger has to be depends on the capacity of your battery. To prevent battery damage manufacturers strongly
recommend you to use a battery charger of adequate capacity. As a rule of thumb, the charging current of the battery charger should
be at least 10% of the battery capacity. This is the only way to get a battery-saving full charge in a reasonable period of time. Here’s an
example: If your battery has a capacity of 150 Ah, you should use a unit with charging current of at least 15 amps (WAECO PerfectCharge
IU 1512 or beyond).
Choosing the right battery charger
Charging technologyProduct informationCHARGING TECHNOLOGY
T
ime (t)
Time (t)