modeling light for Norman LH 500 heads

Is anyone running a 250w modeling bulb in these heads without any problems? I know it can handle

150w and on Adorama's page they have a 250w bulb as an accessory for the LH500 along with the 150

bulb so I'm wondering if it is okay to use the 250w.

I check the Norman site but it seems to suggest the 150 is what is included with a new head with no

actual specs as to what the head can handle.

Anyone with some electrical knowhow that could help me here?

Thanks in advance.