SYSTEM 238 Installation Manual
3
Earth Ground
To ensure the effectiveness of the lightning and transient protection
circuits, the control panel must be connected to "Earth Ground".
Ideally, this should be a common ground to the power lines, telephone
system, and security system. This type of ground, called a "Unified
Earth Ground", provides the best protection. The ground connection,
from a grounding rod, cold water pipe or other established ground
point, is made to the green jacketed wire providing a ground to the
panel housing.
WIRING THE PANEL
Standby Battery
The SYSTEM 238 is designed to operate with a 12 volt, 6.5 Ah, sealed
lead-acid battery (C&K Model 1265). Do not use non-rechargeable
batteries or batteries other than sealed lead-acid. It is recommended
that you replace the standby battery every three to five years.
Connect the red lead to the battery positive terminal and the black lead
to the battery negative. The battery is reverse-polarity protected by a
3 AG, 3 amp, fast-blow fuse (F4).
NOTE: If any fuse opens, remove AC and DC power, remove
the short or overload condition, then replace the fuse
before restoring power. Do not substitute a higher
rated fuse.
Electromagnetic Interference
Vibrating horns can produce electromagnetic interference (EMI). While
EMI will not damage the SYSTEM 238, it can cause transmission
errors and mis-dialing. To minimize EMI, install a 0.01 mfd, 100 volt
capacitor across the terminals of the horn. The capacitor must be
located in the horn.
AUXILIARY POWER
The SW/AUX terminal provides positive 10 - 12.5 VDC
power for devices that require switched power for reset-
ting. Typical devices are glass-break and smoke detec-
tors.
The C terminal provides power common.
The AUX terminal supplies uninterrupted positive power.
Fuse F2
The SW/AUX and AUX terminals are protected by a 0.75 amp, 3 AG,
fast-blow fuse (F2).
The KEY+ terminal (red) provides 11 - 14 VDC keypad power.
The DATA terminal (green) is data from the keypad to the panel.
The C terminal (black) is common.
ARMING STATIONS
The CLK terminal (white) is the clock line.
Maximum wire length for connecting any keypad is 500' (152 m) of 22
AWG (0.643 mm) copper wire.
The SYSTEM 238 is capable of addressing up to 8 Alpha keypads.
LED keypads do not require addressing. Each LED keypad uses 35 mA
of current. Each LCD keypad uses 64 mA of current. See Available
Power for current limitations. See page 4 for additional information on
keypad setup.
Terminal Labels:
SW/AUX, C & AUX
Terminal Labels:
C, KEY+, DATA, & CLK
LOOP INPUTS
Each loop is independently
configured through pro-
gramming. Loops can be
wired with an open circuit
switch, or closed circuit
switch, or with a 2.2K ohm
end-of-line (EOL) resistor.
When programmed as
EOL, either an open or a
short will be reported as
an alarm if the system is in
an armed state.
-
+
N.O.
Alarm
N.C.
Alarm
EOL Loop
Terminal Labels:
Z 1 - Z 8 & C
Fuse F3
The KEY+ terminal is protected by a 0.75 amp, 3 AG, fast-blow fuse (F3).
Terminal Label:
AC
AC power is supplied by a 16.5 VAC, 25 - 40
VA transformer at 50 or 60 Hz. The transformer
must be a UL listed Class 2 transformer. Connect
the secondary of the transformer to the terminals labelled AC. Use
at least 18 AWG (1.02 mm) wire to reduce voltage drops. The
primary side of the transformer must be connected to an
unswitched receptacle. Do not connect primary to Ground-
Fault-Interrupt (GFI) circuits. Secure the transformer to the wall.
AC POWER
AC Power Failure
If an AC power failure lasts more than 15 minutes, the keypads will
display a system trouble. An AC failure report will be sent, if pro-
grammed. When AC is restored for five minutes, a restoral report will
be sent.
Precautions
Do not share the secondary of the transformer with other
devices. A foreign ground can damage the power supply,
voiding the warranty.
Do not use any transformer other than that specified in
the AC POWER section above.
Available Power
The maximum total power available from the Audible, AUX (Switched
and Unswitched), and Keypad is 800 mA. The switched auxiliary,
unswitched auxiliary, and keypads share the same power bus.
Combined power for these outputs should not exceed 500 mA**.
NOTE:
The 50 mA switched power available on Loop 8 is
part of the total 500 mA AUX power.
** To comply with UL 365 and UL 609, this value must
be reduced to 150 mA.
Terminal Label:
BELL & C
AUDIBLE OUTPUT
The BELL terminal provides up to 1.3 amps at
10.5 - 13.5 VDC . The type of voltage (steady,
pulsed, chirp) and the time is programmable.
Fuse F1
The BELL terminal is protected by a 2.5 amps, 3 AG fast-blow fuse (F1).
