Introduction

All the external sounders we supply, with the exception of the Klaxon Masterblaster, have the following features.

• One or two Piezo sounders emitting between 109dB and 118dB. Note that the decibel (dB) scale is logarithmic and as such a small increase in the dB level can be heard as a significant change in the loudness of the sound. The commonly accepted value for the pain threshold is approx 120dB, at which the hearing can be damaged. On perusing the external sounders we supply you may have noticed that some sounders are available in two versions e.g. Texecom Odyssey and Odyssey 'E'. The 'E' version has one Piezo sounder whereas the standard Odyssey has two Piezo sounders.
• A Strobe light. This is a high intensity strobe light which flashes at approx 1 flash per second. Note that the Strobe light will continue to flash after an alarm condition, and after the sounder has timed out, until it is reset at the control panel.
• A Self Actuating Bell (SAB) unit. This unit comprises a rechargeable battery and charging circuitry, and a tamper circuit. The control panel trickle charges the battery and also holds off the sounder. When the alarm is triggered, the hold off is removed and the sounder is powered from the control panel. If the connection to the sounder is removed then the sounder will operate on its internal battery. On most external sounders the unit can be set to operate in Self Contained Bell (SCB) mode. This mode is used when more than one sounder is connected to the alarm system. In SCB mode the sounder draws its power from its internal battery and thus does not overload the control panel. Thus with two or more sounders connected, one should be set as SAB and the second and subsequent sounders set to SCB mode.
• A cut-off timer. UK legislation limits the duration of the audible alarm to a maximum of 20 minutes, and as such all external sounders have an automatic cut-off at 20 minutes or less. Note; under normal alarm conditions the duration of the sounder is controlled by the control panel. It is only when the connection between the control panel and sounder is broken that the sounder will operate on its internal battery and its internal timer then comes into effect.
• Comfort LEDs. The majority of sounders have flashing comfort LEDs which alternate at around 1 second intervals. Their pupose is twofold - the correct flashing pattern indicates that the sounder is operating correctly and that its battery is charging and the flashing indicates that the sounder is live to a would-be intruder.

  See also

  Compare External Sounders