Replace a Wheel

All models of Optec filter wheels use the same methods for removing and replacing the wheels. The IFW filter wheel can easily be removed from the IFW system without tools or removal from the telescope. A hinged door is secured by a single captive thumbscrew. Once opened, the wheel can be extracted and another inserted in its place. The entire process takes only a few seconds. Hitting the HOME switch on the hand control or invoking the HOME function in the operating program will set the wheel to position one and bring up the available filter names for that wheel.

The wheel is held in place by a center shaft which is spring loaded and can be pulled from the wheel by use of a small pull knob on the back of the wheel housing. Rotating the pull knob counter clockwise will allow the spring shaft to retract from the wheel. At that point, the door can be opened and the wheel removed by hand. A different wheel is inserted and the pull knob turned clockwise until the shaft falls into the wheel center bearing. Proper operation of the wheel is dependent on the friction for the O-ring and motor shaft. If the pressure is too light or too heavy, or if there is oil or grease on the O-ring, the wheel will not rotate properly and an error condition will occur. Usually, cleaning the O-ring will solve this problem. See Section 6.0 for troubleshooting information. It is a common mistake to put the filter wheel in backwards. If this is done the filter wheel will not rotate. Make sure the numbers and markings on the filter wheel face the telescope when inserting the wheel.