2.2.4
Battery Supervision
Each DACT shall constantly monitor and supervise its battery power supply.
A low battery or trouble message shall be transmitted when battery voltage
under load falls below 85 percent of the rated battery voltage, but in any
case prior to the point at which the battery will fail to operate the
transmitter. This message shall be included as part of every subsequent
transmission until the problem is corrected if the battery is the primary
source of energy powering the DACT.
2.2.5
Trouble Supervision
Disarrangement of the DACT wiring which prevents proper operation of the
DACT, or the abnormal position of any switch shall cause transmission of a
trouble message and actuation of a local audible trouble alarm. DACT shall
have a switch to silence the audible trouble alarm, however, while the
audible alarm is silenced an amber trouble lamp shall remain lit. Upon
correction of the trouble conditions, the audible alarm shall again sound
until the silencing switch is returned to normal, or the silencing switch
may be the momentary action, self-resetting type.
2.2.6
DACT Power Supplies
**************************************************************************
NOTE: the voltage available at each building must
be verified. If 120-volt service is not available
at certain buildings, the need for transformers
shall be noted on the contract drawings.
**************************************************************************
Each DACT shall be powered by locally available 120 VAC power. Upon loss
of AC power, the transmitter shall automatically and instantaneously switch
to standby battery power, without loss of any alarm signals. Loss of AC
power shall also cause the local audible trouble alarm to sound [and a
trouble message to be transmitted if power is not restored within [1]
[_____] minute[s]]. Upon restoration of AC power, transfer back to AC
operation and silencing of audible trouble alarm shall be automatic. Power
supply filtering shall prevent false message transmissions caused by
transient or steady-state electrical disturbances.
2.2.6.1
Battery Power Supply
Batteries shall be spillproof, sealed lead acid or lead calcium. The
battery package shall be capable of supplying power requirements of the
DACT. DACT standby battery capacity shall provide sufficient power to
operate the transmitter in a normal standby status for a minimum of 60
hours and be capable of transmitting an alarm signal at the end of that
period. Batteries shall be located within the DACT housing.
a.
Converter/float charger: Under presence of 120 VAC power, DACT
batteries shall be charged through a converter/float charger.
Charger shall recharge a fully discharged battery in not more
than 48 hours while the transmitter is operating under normal
conditions (presence of 120 VAC power), or provide a charger which
maintains a battery at full charge under normal daily testing
load and provide batteries having capacity for 6 months field
service without recharge.
SECTION 13854N
Page 13
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