★安装于系统通讯总线上，用于通讯总线线路的短路故障隔离，一台 HDM3310总线制消防电话总机最多可连接 30

部 HD374总线隔离模块， 每部 HD374模块后的通讯总线可连接 30部总线制编码消防电话分机或消防专用墙孔。

★ HD374隔离模块所连接的输出线路具有短路保护和隔离功能，并可不影响其他通讯总线回路的正常工作。

★ 采用 86接线预埋盒安装结构。

★ Installs on system bus-line, is used to isolates bus-line failure, each HDM3310 exchange can connect up to 30 HD374 isolators, each isolator can support 1 to 30 fire telephone extension or wall socket. ★ HD374 isolator provides protection for following bus-line section from short-cut situation, and also keep rest section of bus-line working normally. ★ Suitable for ‘86’ type box installation.