3
Entry-Master Option-4 Hardware Installation Guide
B. Power Instructions
1. The Option-4 board can be powered by AC or DC, from 12V up to
24V input. However, the Option-4 board only provides a maximum
of 12V DC on any of its outputs, and 5V for iButton reader power.
2. It is strongly recommended you use a 12-volt AC power
transformer with at least 20-volt-amps (VA) of output power. If the
VA rating is higher than 20 the Option-4 circuit board will only draw
the power it needs.
3. You will notice above the P1 Power label on the Option-4 circuit
board there is not (+) or (–) but a (~) symbol under each pole of the
blue connector. Because the Option-4 circuit board can use either
AC or DC power, polarity is not an issue. Either pole can handle
(+) or (–) current. Note that this is not the case with the battery
back up located to the right and labeled BT2 Battery. Polarity is
important when connecting a battery back up.
4. The Option-4 board will retain its memory (i.e. token holders,
access groups, time zones, etc.) in the event power is lost.
However, there is no real-time clock on the Option-4 board, so a
power loss resets the board's date and time to a default date. For
this reason, it is highly recommended that a battery backup be
used! For battery back up you must use a 12-volt gel cell battery.
The (+) terminal of the battery must be connected to the blue screw
on the connector labeled (+) and the (–) terminal of the battery must
be connected to the blue screw on the connector labeled (–).
5. Listed below are the Electrical Specifications for the Option-4 circuit
board:
