Sensaphone Express II - Manual (Page 14)

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Sensaphone ® Express II User’s Manual
STRAIN RELIEF
Strain relief clamps are provided on the Express II enclosure to prevent wiring from being
pulled from the circuit board or damaged when passing through the enclosure. To use the strain
relief, thread wires through the clamp and the clear rubber bushing. Position the bushing in
the clamp and tighten the screws on either side so that the wiring does not move. See Figure 2
below:
Figure 2: Strain relief clamp
POWERING UP
Express II is provided with a 12V AC power transformer. This should be plugged into a 117V
AC outlet, +20%, 60HZ.
The transformer is pre-wired to the terminals labelled AC.
GROUNDING AND POWER SURGE PROTECTION
Express II should be earth grounded by connecting a true earth ground to the terminal labeled
EG. This is not essential for Express II to operate, but it is necessary to prevent possible
damage by a lightning strike.
The Sensaphone Express II can be damaged by power surges and lightning through the
telephone line and the power supply. Although Express II has built-in surge protection, we
strongly recommend that additional protection be obtained for the unit and for any electronic
equipment that is attached to your power supply and telephone lines. Power surge protection is
especially important if you live in a lightning-prone area. Surge protection is available through
Phonetics, Inc. Call for details.
BACKUP BATTERY
Express II has a 12V 3AH sealed lead-acid Gel-Cell rechargeable battery. This will provide
approximately 6–12 hours backup time. Actual backup time will depend upon the number of
input/output cards installed in the unit, the number of sensors being powered from the unit,
temperature, battery age, and dialing activity. The battery comes pre-wired with the red wire
attached to the BAT IN(+) terminal and the black wire attached to the BAT IN(-) terminal.
Express II will automatically charge the battery whenever the power switch is turned on and the
power transformer is plugged in. The unit also includes special circuity to prevent the battery
from being damaged in the event of an extended power outage. When the battery runs down to
9V, the unit will automatically disconnect it, preventing deep-discharge damage. The battery
will remain disconnected until it charges back up to 12.3 volts. The battery should provide 5
years of service before needing replacement.
NOTE: Have battery serviced by qualified service personnel only.