Wiring; Power Input; Battery Backup - Recognition Systems HANDKEY II Manual

Planning an Installation

Wiring

Four basic circuits typically connect to the HandReader:
•

Power Input

• Door Control Inputs and Outputs
• Networking and Communications
• Card Reader Input and Emulation Output
Power Input The HandReader requires 12 to 24 volts DC (600 mA) or 12 to 24 volts AC (7
watts). Power can be connected either to the power terminal pins 1 and 2 or
through barrel jack J12.
Terminal 1 and the center pin of power jack J12 are connected together.
NOTE
Terminal 2 and the sleeve of power jack J12 are connected together.
A full-wave bridge rectifier input structure is used in the power supply of the
HandReader, making the polarity of terminals 1 and 2 irrelevant. Recognition
Systems recommends using terminal 1 for positive (+) voltage and terminal 2
for common (-) for consistency. If J12 is used to attach power with the optional
Recognition Systems wall-mount power supply, terminal 1 will reflect +13.8
VDC (unregulated) and terminal 2 will be power supply common.
NOTE Neither terminal 1 or terminal 2 is connected to the HandReader ground.
Do not connect a HandKey's power supply to a switched duplex outlet. The
NOTE
HandKey must have a constant source of power for proper operation.
Battery The HandReader uses an internal switching regulator to obtain internal
Backup operational power. It accepts input voltages from 12 to 24 VDC or 12 to 24 VAC
at 50 to 60 Hz. An optional power-fail protection circuit board can be attached to
the main circuit board to provide and control battery backup. The design of the
internal power supply is such that any range of the above input voltages may be
used and still provide proper battery charge voltage and battery backup
operation. Switch-over to battery power is automatic and occurs when the input
voltage falls to approximately 10.5 volts. At that time the internal battery charger
is disabled to save power and uninterrupted operation continues on battery
power.
When input power is restored, the HandReader switches off of battery operation
and the battery charger is re-enabled to recharge the battery. Battery charge
voltage is set at approximately 13.65 volts, and battery charge current is limited
to approximately 50 mA. A fully discharged battery requires approximately 12
hours of charge to fully recover.
Additional options installed and specific configurations within the HandReader
make it difficult to predict precisely how long battery support will last, but in
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