Balance

Especially in the case that asymmetric instruments (like ALFOSC) are mounted on the adapter there is a risk of damage to the rotator drive if the telescope power is lost while pointing away from zenith. The rotator balance was checked for no-instrument, ALFOSC, NOTCam and MOSCA. In general, there is no space to move the around the things that are already permanently mounted on the rotator and or the instruments and a separate fixture was designed for weights to be added after mounting an instrument. Tests indicate that weights in the range 25-50kg are needed. The new fixture is being prepared and will need to be tested.