The Bosch LBB 1992/00 Plena Voice Alarm Router is an expansion unit that can add six zones and 12 input contacts to the Voice Alarm System. It can use the built-in amplifier on the LBB 1990/00 Voice Alarm Controller and provides inputs and outputs for one or two amplifiers in a multi-amplifier one or two-channel system. The LBB1992/00 provides dual-channel operation for calls and BGM simultaneously to a maximum of six different zones, using two Plena amplifiers. Additionally, the single-channel operation is possible with only one Plena amplifier. Multiple routers can also share one amplifier, including the internal amplifier on the controller unit. It is possible to use any number of amplifiers from one up to the number of routers used. The controller supports A/B wiring. Expand the voice alarm system with six zones EN 54‑16 certified and EN 60849 compliant 12 additional input contacts Six volume override output contacts Supervision within the Plena Voice Alarm System Up to 9 routers can be used Same functionality as the system controller Uses System controllers built-in amp or additional Plena booster amps