DSC maxsys PC4020KT, System Manual

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5
Battery Troubles
If a zone has a low battery trouble, then that zone does
not report in with a zone supervisory within the
"supervision time". The zone will not go into alarm. This
has been included to reduce the possibility of a false
alarm from batteries that do not get changed in the
zone, and then the zone going into sensor fault.
Restoring Battery Troubles
A wireless zone battery trouble will only be restored
after that zone has been Tampered and Restored. This
will allow the batteries to be changed without multiple
Battery trouble/Battery restoral transmissions taking
place. In order for the batteries to be changed the cover
must be removed from the back plate (tampering the
zone). When the tamper is restored and the zone sends
a battery trouble restoral (as well as the tamper restoral)
signal to the PC4164, the battery trouble will clear.
Default Srl #'s (4)
Once this selected has been made the LCD will display
the message "Confirm Default Press
✱
". To abort press
any other key. Once the [
✱
] key has been pressed the
LCD will display the message "Resetting ". All RF zone
signatures will have been erased from the PC4164.
Note: Deleting the RF signatures from the PC4164
will not remove the zone(s) from the partition
assignment(s).
COMBUS Power and Operation
The PC4020 main board can provide up to 500 mA to
power modules, keypads and devices. A PC4204 power
module is required when additional current is needed
either for powering detection devices or operating bells
and sirens. The PC4204 requires its own transformer
and battery and can provide up to 1.5A at 12 V
DC
. Four
relays on the module provide form C switched outputs
with contact ratings of 3 amps @ 12 V
DC
(10 amps @ 120
VAC) for a variety of programmable options. When used
to repower the COMBUS the PC4204 must be wired in
accordance with the instructions supplied with the unit.
Use of a power source other than the PC4204 power
supply module to supply additional power to the PC4020
system is not recommended for the following reasons:
If the main panel loses communications with a module,
within a maximum of 30 seconds the panel will perform a
system reset in which power to the COMBUS is
removed. Five seconds later power is reapplied and the
panel will attempt to communicate with the module. If
the panel is unsuccessful communicating with the
module it will display and report a COMBUS
communications fault.
When the main panel performs a reset, relay 1 when
programmed for “COMBUS POWER” will open. This will
disconnect the power supplied to the modules, resetting
them so that communications to the main panel are
reinitialized.
For example, if the microprocessor on the module has
been scrambled due to a transient, the PC4020 will
power down the COMBUS, the PC4204 will mimic the
PC4020 and cut off its power supply to the module. The
module will be powered down. When the PC4020 returns
power to the COMBUS, the PC4204 will reconnect its power
supply, and the power to the module will return. Because
the module was powered down and powered up, the
module is now reset, and can communicate with the
PC4020.
If a power supply other than a PC4204 was used, the
module would never power down, never reset, and the
module will stay off line requiring the attention of service
personnel.
CAUTION: When used to power a module, the “RLY 1
COM” terminal of the PC4204 must be connected to the
“RED COMBUS” terminal of the module only. The
positive (RED) conductor of the COMBUS must be left
unconnected to the module that is powered by the
PC4204. The “BLK COMBUS” of the module should be
run common to the negative (“BLK”) of the COMBUS.
Use of a power source other than the PC4204 power
supply module to supply additional power to the PC4020
system is not recommended.
The COMBUS is a four conductor cable to which all
modules and keypads are connected in parallel.
Connections to the COMBUS do not have to be home-run.
For example if a storage building had an 8 zone expander
(PC4108) and a keypad (LCD4500 ) located in it, the zone
expander and keypad could be spliced together and run
back on a single 4 wire cable to the nearest point on the
COMBUS.
KEYPAD
R
B
Y
G R
B
Y
G
R B Y G
COMBUS
PC4020 PC4108
Testing The Combus
To test the Combus for a low voltage condition, connect all
devices to the system (include any motion dectectors, glass
break detectors, etc.) and enroll each of the modules. Exit
installers mode and allow the system to run normally for 5 -
10 minutes. This will allow time for any modules that may
have battery troubles time to report. If after this time there
are any battery troubles be sure that the batteries are
"good" by disconnecting the suspect battery and placing a
voltage meter accross the battery leads (of the module); the
output voltage should be 13.85V. If the voltage is good then
check the battery (under load), even if the battery is under
a load the voltage should still be above 12.0V. Once all (if
any) battery troubles have been taken care of, be sure that
there are no Combus Low Voltage troubles. If there are
locate the modules with the low voltage troubles by entering
Installers Mode and selecting Diagnostics. Refer to
Appendix B for the List of Diagnostics. Once the module(s)
have been isolated a PC4204 will be required to increase
the power to be module with the low voltage trouble. Now
that all trouble have been taken care of the next step is to
remove AC power from all modules and allow the panel to