Piezoelectric electronic audible alarms work by converting the user input voltage to an appropriate oscillating signal that is applied to a sounder element that is mounted in a housing. This piezoelectric sounder element consists of a metal disc that has a special ceramic material bonded to it that physically bends when voltage is applied to it.
| Specifications | |
| Operating Voltage | 30Vpp Max. |
| Rated Voltage | 5Vpp |
| Resonant Frequency | 750 ±250Hz |
| Capacitance | 70nF ±30% @ 120Hz |
| Current Consumption | 1.5mA Max. @ 5V⎓ |
| Sound Pressure Level | Min. 87dB @ 5V⎓, 10cm |
| Dimensions | 14 × 60mm (44mm Wide w/o Mounting Ears) |
| Mounting Centers | 52mm (Hole Diameter 3.5mm) |
| Wire Gauge | 28 AWG |
| Operating Temperature | -20° to 70°C (-4° to 158°F) |
Direct drive transducer devices do not have any included DC circuitry, so the user must apply a sine or square wave with the appropriate rated frequency. A square wave will typically result in more sound level than a sine wave. The higher the peak-to-peak voltage applied (up to the maximum rated voltage), the higher the resulting sound level.