United Technologies Edwards 3-ZA20A Assembly instructions

© 2019 United Technologies Corporation 1 / 4 P/N 387463-EN • REV 005 • ISS 18MAR19
3-ZA20A, 3-ZA20B, 3-ZA40A,
3-ZA40B Zoned Audio
Amplifiers Installation Sheet
Description
The 20 and 40 watt zoned audio amplifier modules are key
components in emergency communication systems that consist of
audible and visible notification appliances. Models are available in
Class A and Class B versions. See Table 1 for a list of model numbers.
The amplifiers provide the following:
•20 or 40 watts of power
•Standard output line levels of 25 VRMS or 70 VRMS
•A 1 kHz temporal (3-3-3) tone to use as an evacuation signal and
a 20 SPM tone to use as an alert signal in the event of a failure of
audio distribution
Each amplifier is also provided with an independently controlled
supervised, power limited 24 VDC NAC circuit. This facilitates the
addition of visual notification appliances to audio notification circuits.
Each zoned audio amplifier requires one space on the rail chassis
assembly.
Table 1: Models
Model
Description
3
-ZA20A 20 watt zoned amplifier
Class A or Class B audio
Class A or Class B 24 VDC outputs
3
-ZA20B 20 watt zoned amplifier
Class B audio
Class B 24 VDC outputs
3-ZA40A
40 watt zoned amplifier
Class A or Class B audio
Class A or Class B 24 VDC outputs
3-ZA40B
40 watt zoned amplifier
Class B audio
Class B 24 VDC outputs
Installation
Install and wire this device in accordance with applicable national and
local codes, ordinances, and regulations.
Caution: Operating the amplifier at an output greater than that
required by the speaker may overdrive the speaker circuit and result in
damage to the equipment.
To install the amplifier:
1.Remove all power from the panel.
2.Set jumpers JP1 and JP2 on the audio power module for 25 or
70 VRMS, depending on the input required by the audio circuit
speakers. See Figure 1.
JP1 JP2
25
VRMS 2 to 3 2 to 3
70
VRMS 1 to 2 1 to 2
3.Set the jumper on the audio amp transformer for 25 or 70 VRMS,
depending on the input required by the audio circuit speakers. See
Figure 1.
4.Slide the module into the required rail/slot position.
5. Gently push the module into the connectors to ensure good
contact.
6.Secure the module to the rail by pushing in the top and bottom
snap rivet fasteners.
7.Connect the field wiring. See Figure 2 through Figure 5.
Note: The gain control pot (Figure 1) should be adjusted to the desired
output levels using a 1 kHz signal after installation. Fully counter
clockwise is maximum gain and fully clockwise is minimum gain.
Figure 1: Jumper and gain control settings
(1) Front view
(
2) Rear view
(3)
Audio power module
(4) Audio amp transformer
(5) Configuration jumper
(6)
Output gain control adjust
(7)
Configuration jumpers

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Wiring diagrams
Figure 2: Typical 25 or 70 VRMS notification appliance circuit wiring
Figure 3: Typical 24 VDC notification appliance circuit wiring
Notes for Figure 2 and Figure 3
1.All wiring is supervised and power-limited.
2.Install listed 15 k Ωresistor on last device only when wired as Class B riser.
3.Polarity designations on connector indicate output signal polarity for circuit supervision. The polarity reverses in an alarm condition.
4.Shield required when audio riser and telephone riser share the same conduit.
5. Twisted pair not required only when audio circuit riser shares conduit exclusively with 24 VDC riser or in conduit by itself.
6.A maximum of 10 Signature Series CC1 or CC2 modules may be installed on the speaker circuit.
7.For maximum wire resistance, refer to the panel installation and service manual or technical reference manual.
8.Synchronization of Genesis strobes is accomplished through the use of G1M, G1M-RM, SIGA-CC1S, and SIGA-MCC1S modules. Refer to the
panel compatibility list.

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Figure 4: Backup amplifier wiring
Notes
1.All wiring is supervised and power-limited.
2.Backup amplifier must be rated greater than or equal to the other amplifiers to which it is connected and must be installed in the same
enclosure.
3.Backup amplifier wiring must be rated greater than or equal to the field wiring used on amplifiers connected to the backup amplifier.
Figure 5: Typical wiring connecting to SIGA-AAxx audio amplifier
Notes
1.Configure the zone audio amplifiers for 25 VRMS
2.A maximum of 16 SIGA-AAxx audio amplifiers may be connected to the output of a single zone audio amplifier
3.Shield required when the audio riser wiring shares the same conduit as the telephone riser

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Specifications
Current
Standby
Alarm
62 mA
1.12 A (3-ZA20A/20B)
2.48 A (3-ZA40A/40B)
Frequency response
400 Hz to 4 kHz at ±3 dB
Harmonic Distortion
< 7%
Audio circuit
Input
Wiring
Output
EOL resistor
8-channel, multiplexed digitized audio:
Class B or Class A
20 or 40 W at 25 or 70 VRMS [1]
15 kΩ (internal on 3-ZA20A/40A)
24 VDC
NAC circuit
Wiring
Voltage
Current
EOL resistor
Special applications
Class B or Class A
24 VDC nominal
3.5 A
15 kΩ(internal on 3-ZA20A/40A)
Refer to the panel compatibility list.
Wire size
12 to 18 AWG (4.0 to 1.0 mm²)
Space requirements
1 rail space
Operating environment
Temperature
Relative humidity
32 to 120 °F (0 to 49 °C)
93% noncondensing
[1] For Canadian installations, 70 VRMS is nonpower-limited.
Regulatory information
Environmental
class
UL/ULC: Indoor dry
Contact information
For contact information, see www.edwardsfiresafety.com.