wrong motor connected to starter

[justajiffy]

I recently joined the plant maintenance dept and one of the first jobs i got was to get a large ventilation fan put back on the roof using a mobile crane.They told me the previous one had burnt out and been sent for a rewind as a 18.5kw star delta motor 3 phase 415v[ uk.voltage]When i connected it up i noticed the starter was an old one but it was two speed high and low.They said yes the old one would only work on high speed but they never used the low speed and the one that was took down was star delta and that worked.There is an identical fan next to it which runs on two speeds there is three contactors and the 6 leads to the motor windings all light to each other.I told them this may be a tapped wound motor,sometimes known as a pole changing motor,and this is how the other motor should be wound.Does anyone know if the star delta motor will be harmed running it from a 2 speed starter as the way i see it is running in star and because it's too much trouble taking the motor off the roof know any wiring diagrams to convert the starter to star-delta if it will harm the motor