User`s manual
Table 2-4 Possible System Configurations
Maximum No. of Keypads
Max Siren Current
Maximum Siren Time
UL Listed?
4
4
4
3
3
2
2
6
8
8
Display + 2 Control
Display + 2 Control
Display + 4 Control
Display + 4 Control
any combination
any combination
any combination
0.5
Unlimited
Yes
1.0
60
minutes
Yes
1.5
30
minutes
No
1.5
30
minutes
No
1.0
60
minutes
No
1.5
30
minutes
No
1 .o
60
minutes
No
1.0
30
minutes
No
1
.0
x
2N”‘“’
30
minutes
No
1.5 x
2N”‘“Z
30
minutes
No
Note 1: Run siren power from battery through a CCU relay. May use both relays, to drive two sirens.
Note 2: Run siren power from battery through an external (higher rated) relay; drive relay from siren driver
terminals.
Sample Configurations
Table 2-4 lists certain possible configurations of
the System, and allows you to see the trade-offs
available between the various devices in accor-
dance with their power usage. You can design a
system that uses up to the number of devices
listed on any one line, but no more than that
number. Note which configurations are accept-
able for UL Listing.
Configuration Calculations
For further flexibility, and since some applications
allow greater power usage in a trade-off for
shorter alarm times, you may calculate allowable
configurations based upon the Non-alarm current
drain and the Alarm Condition current drain:
I, =
.07
times (No. of DK) +
.05
times (No. of CK) + Aux
IA
=
.15
times (No. of DK) +
.06
times (No. of CK) + Aux + Siren
where:
IN
is the Non-alarm current,
No. of DK is the number of Display Keypads,
IA
is the Alarm current,
No. of CK is the number of Control Keypads,
Aux,
is the Non-alarm current from the Aux
supply (Aux, is alarm current), and
Siren is the total siren current drain.
Table 2-5
Power Usage versus Alarm Times
Non-Alarm
Current
Alarm Current IA
1,
1.5
2.0
2.5
1.5
Unlimited 10 mins. 5 mins.
1.2
Unlimited 30 mins. 15 mins.
1 .o
Unlimited 45 mins. 20 mins.
0.7
Unlimited 60 mins. 30 mins.
These limits are valid for a temperature environ-
ment of
40%
maximum for the transformer.
In Table 2-5, read across from your I, (column 1)
and read down from your I, to find the length of
Alarm Time that system will provide. If the time is
too short, you must find a way to reduce the I,
and/or
IN.
2-10
AT&T Security System 8300 Installer’s Manual