Yeastar S-Series VoIP PBX
Yeastar S-Series VoIP PBX offers a scalable solution that is easy to install and manage and that has been built to provide the ultimate performance quality. Targeted for small and medium size enterprises, the Yeastar S-series PBX can support a range of 20 to 300 users and 10 to 60 concurrent calls. Future proof your business and your investment with the S-series PBX; built to meet all of your current communications needs, but also built with a modular design that is highly flexible.  S-series offers advanced failover protection as well as monitoring and reporting capabilities. The S-Series PBX can be configured with any of the telephony interfaces below. The S20 supports 2 modules without expansion boards, S50 supports 4 modules without expansion boards, S100 supports 8 modules=2 expansion cards, and S300 supports 12 modules=3 expansion cards.One Expansion card can support 4 modules. On S100 and S300, you must install expansion boards if you want to add modules or PRI port.The S100 and S300 support the D30 module to add 100 users and 30 calls.