Industrial control system including - a controller, - an equipment to be controlled by the controller, - a wireless network having a wireless master wire-connected to the controller and a wireless slave wire-connected to the equipment, wherein - the controller is designed to perform timing control of the wireless master according to a timing protocol, - the wireless master is configured to terminate the timing control and to transmit a system time value to the wireless slave, - the wireless slave is designed to synchronize to the wireless master and to initiate timing control of the equipment according to the timing protocol on behalf of the controller, characterized in that the wireless network being configured to perform the following steps for synchronising the wireless master with the wireless slave: - step a): transmitting a pregiven scheduled transmit time period ( T UL_SCH) to the wireless slave, - step b): transmitting synchronisation data from the wireless master to the wireless slave, - step c): setting a transmit timing of the wireless slave in dependency of the pregiven scheduled transmit time period ( T UL_SCH) and a parameter ( T̂ d), - step d): transmitting a uplink signal (IRT u) from the wireless slave to the wireless master in accordance with the transmit timing, - step e): measuring an arrival time (t IU) of the uplink signal (IRT u) with respect to the transmitting of synchronisation data of step c), - step f): computing adjustment data by the wireless master on the basis of the arrival time and the pregiven scheduled transmit time, - step g): transmitting the adjustment data from the wireless master to the wireless slave in a downlink signal (IRT d), and - step h): adjusting the parameter ( T̂ d) of the wireless slave in dependency of the adjustment data and repeating at least step c). - a controller, - an equipment to be controlled by the controller, - a wireless network having a wireless master wire-connected to the controller and a wireless slave wire-connected to the equipment, wherein - the controller is designed to perform timing control of the wireless master according to a timing protocol, - the wireless master is configured to terminate the timing control and to transmit a system time value to the wireless slave, - the wireless slave is designed to synchronize to the wireless master and to initiate timing control of the equipment according to the timing protocol on behalf of the controller, - step a): transmitting a pregiven scheduled transmit time period ( T UL_SCH) to the wireless slave, - step b): transmitting synchronisation data from the wireless master to the wireless slave, - step c): setting a transmit timing of the wireless slave in dependency of the pregiven scheduled transmit time period ( T UL_SCH) and a parameter ( T̂ d), - step d): transmitting a uplink signal (IRT u) from the wireless slave to the wireless master in accordance with the transmit timing, - step e): measuring an arrival time (t IU) of the uplink signal (IRT u) with respect to the transmitting of synchronisation data of step c), - step f): computing adjustment data by the wireless master on the basis of the arrival time and the pregiven scheduled transmit time, - step g): transmitting the adjustment data from the wireless master to the wireless slave in a downlink signal (IRT d), and - step h): adjusting the parameter ( T̂ d) of the wireless slave in dependency of the adjustment data and repeating at least step c).