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User's manual for
3.3.
POWER SUPPLY
Fig. 3.2. Power supply connection of
controller
Main power is supplied by a toroidal transformer - minimum 150VA and nominal output
voltage 24VAC.
•
It is necessary to protect the transformer primary winding circuit with a 2A fuse.
•
Never use transformers having idle secondary voltage higher than 27 VAC
If door operation is required also during mains failure a 24V battery of minimum 1.2Ah
capacity must be connected externally. Use of two standard 12V batteries connected in series
is possible. An automatic battery charger circuitry is a part of the controller board and is
designed to charge battery with 200 mA current, which is sufficient to keep the battery fully
charged, but will not be able to quickly charge fully discharged batteries. If main power supply
fails then LCD backlight and motor will be switched off and
will continue operating on
battery. When the battery voltage drops below certain threshold (19V) the controller will shut
down.
Battery connection is not mandatory and the controller can operate normally without it,
however the battery voltage read-out on the LCD will be displayed incorrectly.
3.4.
MOTOR
controller
8
J1
Motor
2 3
1
Battery
24V 1,2A h
- +
J3
1 2
~ 230V AC
FUSE
1 2
J2
~ 24V AC