• With perfect detection measures, it can detect the bus short circuit and open circuit of each channel and give sound and light alarm. After troubleshooting, it can be automatically reset. With self-test function, it can detect display and sounding devices.

• The host and extension can call each other and have full duplex calls. The multi-party can talk, and the host can call the 2 part machine or the 2 part machine at the same time to call the host and talk to it. The host hands-free call.

• It has the function of recording and displaying the call and response time; and can query and display the records of 100 host and extension calls and response time. Advanced digital recording technology, high reliability, long life, automatic recording of calls.

• Working environment: temperature 0 ~ 40 ° C, relative humidity less than 95% RH.

• Power supply: DC24V±10%; working current: ≤1A

• Voice response: 300~3400Hz (±3dB)

• Transmission loss: ≤5dB

• Line condition: extension loop resistance (without telephone) ≤300Ω; insulation resistance between lines ≥20kΩ

• Bus length: ≤1000 m

• Recording time: more than 20 minutes

• Capacity: 20 doors, 99 doors optional