Capacity is partially a matter of quality versus quantity. Increasing capacity utilization gives more scheduled waiting time in the timetable as well as more delays when trains are operated. A common way to analyse capacity is to first make a timetable and then use it in a simulation where trains are perturbed. This way it is possible to establish the scheduled waiting time and the expected delays of the trains at the same time as market demands on traffic, e.g. frequency of different train services, are considered. However, setting up simulations are often time consuming and requires a lot of input data.A method is developed with the objective to improve and speed up capacity analysis of double track railway lines. It can be used for both timetable generation and timetable simulation. The focus of this paper is to present the model and validate that it can simulate timetables accurately. The model has a macroscopic representation of the railway infrastructure and rolling stock while timetables and perturbations are modelled in more detail. When resolving conflicts, the dispatching algorithm can consider several trains and take into account how the dispatching decision affects the possibility to make good decisions at the next station.The validation is performed using the micro simulation tool RailSys as reference. The validation covers a wide range of scenarios of different traffic density, timetable heterogeneity, inter station distance and primary delays. The validation shows good results and the conclusion is that despite the simplicity of the model, it is accurate enough to use in capacity analysis