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Procedures specific to removal of FIF from tracker are given
in italic font.
Goals:To relocate FIF from Prime Focus to Home Away From Home, the Ramsey Rack or the floor. Installation is the reverse of the removal procedure
Equipment and Conditions Required:
Responsible Party:Jim Fowler
Procedure:The FIF may be relocated to Prime Focus, to Home Away From Home, hanging from the Ramsey rack, or down to the floor. The basic procedure is the same for all with only additional steps required as one gets further from prime focus.
Set the structure to Engineering North at 350 degrees (325 structure coordinate).
Attach the Fiber Support Arm to the FIF Lifting Fixture if the FIF is to be taken to the Ramsey Rack or the floor.
Lower the dome crane and attach the FIF Lifting Fixture. If the Fiber Support Arm is attached, the lifting straps should be connected to each beam. Raise the fixture as high as the crane will go. The dome should be positioned counterclockwise of the tracker midline. Around 255 degrees is good. PUT A PICTURE HERE OF THE LIFTING FIXTURE ON THE CRANE.
The JLG driver and assistants will take the JLG to the tracker and attach the safety strap. Drop off one person at the upper side of the payload. If the FIF is to moved off the tracker, then the FIF electrical cables will need to be removed. Disconnect the electrical cables from the FIF electronics box. Cut the tie wraps holding the cables to the carriage beam. Lower the cables gently until they hang from the Fiber Support Bracket being careful not to let the cables drop. PUT A PICTURE HERE OF THE ELETRICAL BOX. The second person should then maneuver the JLG and drop off on the lower side of the payload. Leave the third person in the JLG basket as a safety.
Have the ground support person move the dome to 275 (or 95 degrees depending on which end of the crane you are using). Note that the fiber support arm will interfere with the electrical cable loop. It will be necessary to hold the electrical cable loop out of the way and maneuver the crane position to clear the cables.
Once the crane is in line with the payload, move the crane so that the FIF Lifting Fixture is over the FIF. Lower the Lifting Fixture slowly to the FIF. The short legs go on the uphill side. Watch out for the cabling on the right side of the FIF as the spacing is narrow. PUT A PICTURE HERE. Remove the leg pins and insert the legs in the FIF lifting ears. Reinsert the pins. Note that the spacing is very narrow and the pins will not insert all the way before they catch on the lifting ears, however the leg pins will still make a locking connection. Ensure that the locking pins are firmly attached. Take up most of the slack with the crane.
Using the 3/16 hex key release the three captive attachment bolts. At prime focus the FIF will remain in the support fixture and not try to fall out.
If the FIF is to move off the tracker, the fibers will need to be connected to the Fiber Support Arm. A third person in the basket is very useful here. Locate the Fiber Support Arm close to the Fiber Support Attachment. Remove the pins in the Fiber Support Arm and the Fiber Support Attachment. Holding the fibers vertical above the Fiber Support, lift the Fiber Support out of the Support Attachment. (Only around 10 pounds of force will be required to lift the support from the attachment.) Insert the Fiber Support into the attachment on the Fiber Support Arm. Insert the locking pin on the Fiber Support Arm. Ensure the pin is securely attached. PUT A PICTURE OF THE FIBER SUPPORT HERE.
Slowly lift the FIF clear of the prime focus support frame. Prevent twisting of the assembly and avoid collisions with the electrical and pneumatic connection on the right side.
If moving to Home Away From Home, rotate the dome approximately 10 degrees clockwise. Lower the unit into the Home Away From Home support bracket. Attach the captive retaining bolts and tighten with the 3/16 hex key. Release the leg locking pins and remove the legs from the lifting ears. Raise the lifting fixture away the FIF to the limit of the crane travel.
If moving to the Ramsey Rack or the floor, install the lower cover plate on the FIF. PUT A PICTURE HERE OF THE LOWER COVER PLATE. Lift the FIF high enough to clear the calibration fibers. Be aware that the FIF fiber length is limited. Monitor the fiber below you and avoid stretching the fiber. Rotate the dome approximately 20 degrees clockwise so that the FIF is in the open area between the tracker and the hexagonal support ring. The crane should be moved outward toward the dome again ensuring that the fiber do not get stretched.
The person at the lower end of the payload should return to the JLG. Move up and pickup the person at the top of the payload. Remove the tracker tie off strap.
If the FIF is going to the Ramsey Rack, move the JLG to the rack area. Slowly move the dome (steps of 5 degrees are good) and the crane to bring the FIF to the rack. Continually monitor the fiber cables for problems. Bring the lifting straps close to the Ramsey Rack hook. Using the 2 inch shackle, attach the lifting straps to the hook. Slowly transfer the load from the crane to the Ramsey Rack. Release the Crane from the Lifting Fixture straps. Return the crane to its storage position.
Return the JLG to the ground. If the FIF is going to the floor, then the fibers will need to be removed from the Guide Bracket on the structure. Using the JLG move to the Guide Bracket. Unlock the swing arm and remove the fibers from the bracket. Relock the swing arm. Avoid moving the JLG under the FIF and crane. PUT A PICTURE OF THE GUIDE BRACKET HERE.
To bring the FIF to the floor lower the FIF with the crane. Lay the fibers along the structure support beams, avoiding sharp bends in the fiber. Use the duct tape to attach the fibers to the beams. The FIF can sit on the structure leg. Use a styrofoam pad underneath to protect the unit. Ensure that the unit is stable and can not be moved. Ensure that the fibers are well supported and will not catch on anything if the structure is moved. PUT A PICTURE HERE OF THE FIF ON THE STRUCTURE LEG.
History:This procedure first written up on 19 Sept 2002 by Jim Fowler.
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