The tandem control system:

─     The tandem control system can be used to control two overhead travelling cranes at the same time using only one transmitter.

─     This means no coordination between crane operators is necessary with the tandem control system.

─     The tandem control system can be used to lift and transport long or bulky loads more easily and safely than with two independently controlled cranes.

─     The tandem control system can be used to lift loads which exceed the maximum load capacity of a single crane of the crane installation. Since the load is shared between the two cranes, the maximum load capacity of the two cranes can be added together. If the load is not distributed evenly, the overall maximum load capacity is respectively lower.

─     The tandem control system evaluates the signals for braking function and shut-down of the travel limit switch on the crane and trolley together. If one of the cranes or one of the trolleys reaches the switching point for the braking function or shut-down function, both cranes, trolleys and hoists come to a standstill (intermediate stop). When travel continues (at the switching point for the braking function) in the same direction, only the low speed can be used.

─     The tandem control system evaluates the hoist limit switch of both hoists together. If one of the load hooks moves into the highest or lowest hook position, both hoists are stopped.

─     The tandem control system evaluates the overload protection of both cranes together. If one of the two hoists is overloaded, both hoists are stopped. This also works where there is an uneven load distribution.

─     The tandem control system signalises with signal lamps on both cranes which crane, which trolley or which hoist is in the limit switch range or has been overloaded. The signal lamps are lit by LEDs and have a service life of around 50000 hours.

─     There is one safety PLC in the crane panel of each crane. The two safety PLCs are linked to one another via light barriers. Through these light barriers, a release signal is transmitted by light path from the transmitter on one crane to the receiver on the other crane and vice versa. This way, the two cranes exchange information (e.g. about whether one of the limit switches has been actuated). The light barriers (one transmitter and one receiver each) are on the end carriage.