The TU849 is a module termination unit (MTU) for redundant configuration of Optical ModuleBus Modem TB840/TB840A.
The MTU is a passive unit having connections for double power supply, one for each modem, a single electrical ModuleBus, two TB840/TB840A and a rotary switch for cluster address (1 to 7) setting.
Four mechanical keys, two for each position, are used to configured the MTU for the right types of modules. Each key has six positions, which gives a total number of 36 different configurations. The configurations can be changed with a screwdriver.
The MTU can be mounted on a standard DIN rail. It has a mechanical latch that locks the MTU to the DIN rail. The latch can be locked/unlocked with a screwdriver.
Termination unit TU848 has individual power supply connections and connects TB840/TB840A to redundant I/O. Termination unit TU849 has individual power supply connections and connects TB840/TB840A to non-redundant I/O.
Features and benefits
• Dual power supply connection
• A rotary switch for cluster address setting
• Mechanical keying prevents insertion of wrong module type
• Single ModuleBus connection
• Latching device to DIN rail for locking and grounding
• DIN rail mounted