RND 305-00016, User Manual

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RND 305-00016 & 305-00017
ENGLISH
Stage 1. THE I-PHASE. The constant current charging, Bulk LED is on.
Normally the batt ery is charged at constant maximum current until it rises to the selected Absorption voltage level.
The charging voltage changes with the batt ery voltage.
If the initial batt ery voltage is less than 9V due to deep discharge, the bulk charge current is reduced to half of the maximum
until batt ery voltage rises over 9V.
Stage 2. THE UO-PHASE. The constant voltage charging, Absorption LED is on .
Batt ery Type Selection: Gel: 14.1V / Wet: 14.4V / Calcium: 15.5V
When the batt ery voltage rises to the selected Absorption voltage level, the charging switches to Constant voltage
charging and batt ery is over 85% full. The batt ery is kept at this high voltage while the current reduces gradually to set value
at which the charger automatically switches to Float Stage.
Stage 3. THE UO-PHASE. The constant voltage charging, Float LED is on.
Float Voltage Selection: 13.2 V / 13.5V / 13.8V
In this stage, the batt ery is full and only takes in the amount of current necessary for maintaining the capacity. The fl oat
voltage is preset independently by user according to the type of batt ery such that batt ery can be connected permanently to
the charger when it is not in use.
E. Manual Equalization Charging for wet type batt ery only
Wet lead acid batt ery requires periodic high voltage charging (about 10% overcharge absorption voltage) to balance the
voltage of each cell, reverse the high concentration of electrolyte at the bott om and clear up large sulfate crystals on the
plates. You can use the Calcium–Calcium selection to perform the manual equalization by carefully following the
batt ery maker’s recommended frequency and duration.
Make sure to manually switch off charger when time is up.
Take special precautions as batt ery will emit explosive gas during equalization charge.
F. Dual bank charging ( RND 305-00016 )
This feature is for caravans, and vehicles with two separate batt eries.
The two batt eries must be of same chemical make up and type to avoid over and under charging because only one sett ing of
charging profi le for both.
Two batt eries are charged simultaneously and the batt ery with the lowest level gets most share of the current in the Bulk
charge stage until it is up to the same voltage level of the second batt ery (batt ery with higher initial level).
Both batt eries will go to the Absorption and the Float Charge at the same time.
G. Power Supply / 2-Stage Charger Mode (see Fig.3)
At this mode the Charger On (5) LED becomes red color and only Bulk and Float LED will function. The bulk LED will be off
when batt ery is charged to about 80% full.
The 3-stage charger becomes a 2-stage charger or as power supply in this selected mode because 3-stage charger over
charges batt ery with external load.
This selected mode is intended for use to charge batt ery with external load such as caravan or other batt ery and external
load combination.
A 2-Stage charger can be used as a combination charger/power supply. An external load can draw current from the charger
while the charger is recharging a batt ery. The charger does not care how much current is being diverted by an external
circuit as it switches from Bulk mode (constant current ) to Float mode based only on the batt ery terminal voltage.
However, a 2-Stage charger cannot completely charge the batt ery when the charger switches from bulk mode to fl oat mode.
Aft er switching to fl oat mode, the batt ery will, in most cases, be about 80% recharged. The batt ery receives the remaining
recharge while in fl oat mode over several days.
It is highly recommended to switch back to the 3-Stage Charger Mode periodically when the external load is disconnected.
Also the external load should not be more than 50% of the max. current of the charger , unless the batt ery is fully charged
up . If the bulk LED is on most of the time then the load is too large.
G1. As a stand alone power supply
It can also be used as a stand alone power supply without connection to a batt ery
It will provide a constant voltage according to the selected Float Voltage (13.2/13.5/13.8V) and rated DC current of the
charger.
However, it is not recommended for high surge load (such as lamp) in stand alone application as the initial high surge current
will trigger the overload protection of the power supply.