Patent ID: 7830798

Claim:
A method for determining a telegram length in an operating apparatus for communicating of telegrams between the operating apparatus and a field device in a field device system, the method comprising: composing a first telegram in the operating apparatus with a predeterminable first telegram length; despatching the composed first telegram via a network to the field device; waiting for a second telegram to be received, via the network, in the operating apparatus; increasing the first telegram length by a predeterminable value until receiving the second telegram fails; and providing the first telegram length that has resulted in successfully receiving the second telegram, wherein at least one apparatus, selected from the operating apparatus and the field device, comprises at least one apparatus selected from the group of apparatuses consisting of a device type manager, a field device tool, a device description, a remote input/output apparatus, a sensor, an actuator, a gateway, a control unit, an elevation device, a fill level sensor, a radar sensor, a microwave sensor, a pressure sensor, a temperature sensor, a flow sensor and a limiting value sensor.