Active alarm built-in power amplifier circuit, the need for external power supply to work properly. Active alarm is usually marked built-in amplifier output power (which requires an external power supply driving power), input impedance and input signal level is equal parameters.

In general, the wiring alarm host access active alarm is: will host DC12V power output interface (or external DC), normally open alarm output interface with active alarm in series to form a loop. DC12V power output (or external DC) can give warning of its internal power amplifier provides the necessary energy source, normally open alarm output is used to control the circuit on and off, in order to achieve synchronization and alarm siren alarm or eliminate Police. Specific wiring method as follows :( attention to the positive and negative can not be reversed)

Internal passive alarm no power amplifier circuit, just a piece of piezoelectric ceramic buzzer, it has to be connected to an audio signal output interface also has a certain drive capability. Generally marked impedance passive alarm, power, frequency range and other parameters.

Passive alarm host access needs built-in power amplifier circuit, directly provide sufficient power output and audio output through the alarm output interface. To drive a passive alarm sound, note the positive and negative alarm can not be reversed.

When the host linkage output interface is not built-in power amplifier circuit, the output power is too small (for example, normally open and normally closed output terminal), you can not drive a passive alarm, but only with the active alarm.