Battery Management - Setec ST20-II User Instructions

ST – II Series POWER SUPPLIES

Battery Management

To maintain the battery in a good state of health an intelligently controlled charging algorithm is
used. The purpose is to ensure that the correct voltages are applied to the battery terminals at the
appropriate times throughout it's usage cycle.
To prevent corrosion on the battery positive plate due to continuous float charging current (VFloat
= 13.65V), the unit utilises a storage mode voltage (VStore = 13.25V) when no activity on the
battery is detected. This extends the battery life. During store mode, the unit exits to boost mode
(VBoost = 14.05V) for 15 minutes every 24hrs to maintain charge in the battery. If battery activity
is detected during store mode it exits automatically into float mode.
For any decision making involving the "loss of mains" detection there is a 2 minute mains debounce
period where there must be no mains signal present on the mains detect input for the "no mains"
signal to be valid.
A detailed description of the operational requirements for the charging algorithm is described
below:
Present Output
Set Voltage
N/A
Vfloat (No Mains
Input)
Vboost
Vfloat
Vstore
Periodic_Vboost
Conditions Required to
Enter Operational State
Microcontroller first power
up.
Mains input detected after
loss of mains for less than
1 hour.
Mains input voltage was
detected for more than 15
minutes.
No mains input voltage is
detected.
No mains input voltage is
detected.
No mains input voltage is
detected.
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Operational State
Initial application of power
to the microcontroller
either from 240VAC mains
input or connection of a
battery to the battery input
(Includes Auxiliary power).
Float charging mode with
mains input voltage
detected (set 24 hour
timer).
Float charging mode with
mains input voltage
detected (set 24 hour
timer).
Float charging mode with
no mains input voltage
detected (set 1 hour timer).
Float charging mode with
no mains input voltage
detected (set 1 hour timer).
Float charging mode with
no mains input voltage
detected (set 1 hour timer).
USER INSTRUCTIONS
New Output Set
Voltage
Vfloat
Vfloat
Vfloat
Vfloat (No
mains input)
Vfloat (No
mains input)
Vfloat (No
mains input)
Issue F