SpectrAlert Selectable Output
CH24MC Series Wall Chime/Strobes
for Fire Protective Signaling Systems
INSTALLATION AND MAINTENANCE INSTRUCTIONS
3825 Ohio Avenue, St. Charles, Illinois 60174
1-800-SENSOR2, FAX: 630-377-6495
www.systemsensor.com
NOTICE:
This manual shall be left with the owner/user of this
equipment.
General Description
The SpectrAlert CH24MC series strobe can be installed in sys-
tems using 24-volt panels having DC or full-wave rectified (FWR)
power supplies. The strobes can also be installed in applications
requiring synchronization (MDL required) or applications that do
not require synchronization (no module required). Please note
that the chime section is not synchronizable with the MDL.
The SpectrAlert CH24MC series chime/strobes are designed to
meet the requirements of most agencies governing these devices,
including: NFPA, ADA, The National Fire Alarm Code, UL. Also,
check with your local Authority Having Jurisdiction for other
codes or standards that may apply.
NOTE: The SpectrAlert CH24MC Series Chime/Strobe must
be powered from a non-coded power supply. This
appliance is not intended for use with a coded power
supply.
Fire Alarm Considerations
Temporal and Non-Temporal Coded Signals:
The American National Standards Institute and the National
Fire Alarm Code require that all horns used for building evacu-
ation installed after July 1, 1996, must produce Temporal Coded
Signals. Signals other than those used for evacuation purposes do
not have to produce the Temporal Coded Signal.
Power Supply Considerations For Strobes
Panels typically supply DC filtered voltage or FWR (full-wave
rectified) voltage. The system design engineer must calculate the
number of units used in a zone based on the type of panel sup-
D900-38-00
1
I56-2477-002R
For use with the following models: CH24MC and CH24MCW
U.S. Patent Nos. 5,931,569; 5.914,665; 5,850,178; 5,598,139; 6,049,446; 6,127,935; 6,133,843; 6,822,400; 6,856,241
Specifications: Chime
Mechanical
Input Terminals:
12 to 18 AWG (3.31 to 0.82 mm
2
)
Overall Dimensions:
6.9
″
× 5.0
″
Electrical
Voltages:
Regulated 12 DC/FWR and
Regulated 24 DC/FWR
Operating Voltage Limits:
8–17.5 and 16–33
Maximum Operating Current
At 12VDC:
31 mA
At 24VDC:
61 mA
Operating Temperature:
32°F to 120°F (0°C to 49°C)
Sound Output:
Sound output levels are established
at Underwriters Laboratories in their reverberant room. Always
use the sound output specified as UL Reverberant Room when
comparing products.
Listings:
UL S4011 Private Mode (Chime/
Strobe), UL S5512 (Strobe)
Specifications: Strobe
Voltage:
Regulated 24 DC/FWR
Operational Voltage Range: 16-33 Volts
Synchronous Applications
with MDL Module:
17-33 Volts
Flash Rate:
1 flash per second
Selectable Light Outputs:
All candelas are selectable via a
manual slide switch. 15/75 is listed at 15 candela per UL 1971 but
will provide 75 candela on axis (straight ahead). 15, 30, 75, or 110
are rated for that candela.
ply. Be certain the sum of all the device currents does not exceed
the current capability of the panel. Calculations are based on
using the device current found in Table 3 and must be the current
specified for the type of panel power supply used.
Wire Sizes
The designer must be sure that the last device on the circuit has
sufficient voltage to operate the device within its rated voltage.
When calculating the voltage available to the last device, it is
necessary to consider the voltage drop due to the resistance of the
wire. The thicker the wire, the less the voltage drop. Generally, for
purposes of determining the wire size necessary for the system,
it is best to consider all of the devices as “lumped” on the end of
the supply circuit (simulates “worst case”).
Typical wire size resistance:
18 AWG solid:
Approximately 8 ohms/1,000 ft.
16 AWG solid:
Approximately 5 ohms/1,000 ft.
14 AWG solid:
Approximately 3 ohms/1,000 ft.
12 AWG solid:
Approximately 2 ohms/1,000 ft.
Example: Assume you have 10 devices on a zone and each
requires 50 mA average and 2000 Ft. of 14 AWG wiring (total
length=ou return). The voltage at the end of the loop
is 0.050 amps per device
×
10 devices
×
3 ohms/1,000 ft.
×
2000
ft =3 volts drop.
The same number of devices using 12 AWG wire will produce only
2 volts drop. The same devices using 18 AWG wire will produce
8 volts drop. Consult your panel manufacturer’s specifications, as
well as SpectrAlert’s operating voltage range to determine accept-
able voltage drop.
Note: If class “A” wiring is installed, the wire length may be up to
4 times the single wire length in this calculation.
Note for Strobes: Do not exceed 1) 16-33 Voltage range limit, 2) Maximum number of 70 strobe lights when connecting the MDL Sync module with a maximum line imped-
ance of 4 Ohms per loop and 3) Maximum line impedance as required by the fire alarm control manufacturer.
