Edwards 3-ZA20A Installation Sheet

Product description
24VDC
Audio power
UNUSED UNUSED UNUSED NAC/B UNUSED
+ -
TB1
module
subassembly
Audio amp
transformer
subassembly
J4
J3
Output gain
adjust
Configuration
JP1
JP2
jumpers
TB2
BACK -UP NAC/A NAC/B
- + - + S - + S - +
Front view
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 networked 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
Number 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 Sheet
3-ZA20A, 3-ZA20B, 3-ZA40A, 3-ZA40B - Zoned Audio Amplifiers
Configuration
jumper
Rear view
3-ZA20A, 3-ZA20B, 3-ZA40A, 3-ZA40B
Specifications
Space requirements: 1 rail space
Frequency response: 400 Hz to 4 kHz at ±3 dB
Harmonic Distortion: < 7%
Audio circuit
Input: 8-channel, multiplexed digitized audio
Wiring: Class B (Style Y) or Class A (Style Z)
Output: 20 or 40 W at 25 or 70 Vrms
EOL resistor: 15 kΩ (internal on 3-ZA20A/40A)
24 Vdc NAC circuit:
Wiring: Class B (Style Y) or Class A (Style Z)
Voltage: 24 Vdc nominal
Current: 3.5 A
EOL resistor: 15 kΩ (internal on 3-ZA20A/40A)
For special applications, refer to EST3 ULI/ULC
Compatibility Lists (P/N 3100427).
Wiring
Termination: Wiring connects to removable terminal block
Max wire size: 12 AWG (2.5 mm sq)
Operating environment
Temperature: 32 to 120 °F (0 to 49 °C)
Humidity: 93% RH, noncondensing at 32 °C
Current ratings
Standby: 62 mA
Alarm: 1.12 A (3-ZA20A/20B)
2.48 A (3-ZA40A/40B)
Installation instructions
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
subassembly for 25 or 70 Vrms, depending on the input
required by the audio circuit speakers.
25 Vrms
70 Vrms
3. Set the jumper on the audio amp transformer
subassembly for 25 or 70 Vrms, depending on the input
required by the audio circuit speakers.
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.
Notes
• The gain control pot should be adjusted to the desired
output levels using a 1KHz signal after installation. Fully
counter clockwise is maximum gain and fully clockwise is
minimum gain.
27JUN07
Zoned Audio Amplifiers
JP1 JP2
2 to 3 2 to 3
1 to 2 1 to 2
P/N: 387463 REV: 4.0
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