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NOTE: It is recommended that you leave the tension as loose as possible for ease of focusing, yet not so loose
that it permits the stage of microscope to drift downward from its own weight and cause the microscope to “drift”
out of focus.
c. Metal parts: Use a clean, damp cloth to remove dust or dirt from metal parts, followed by a dry cloth.
3. ELECTRICAL MAINTENANCE
The extent of electrical maintenance, by other than a qualified technician, should be bulb replacement. BE CERTAIN
TO TURN SWITCHES OFF AND REMOVE PLUG FROM POWER SOURCE OUTLET BEFORE CHANGING
BULBS.
a. Changing bulb on Models 131 & 132
Make sure that illuminator field lens housing and lamp are cool before attempting to remove. Remove illuminator
field lens housing by rotating in a counter-clockwise direction. This housing is secured tightly, to prevent easy
removal by students, so a very firm grip and some strength will be required.
Note that lamp does not screw out. Remove lamp by depressing lamp slightly and rotate in a counter-clockwise
direction until it pops up slightly. Replace with a 110v 20 watt lamp with double contact, medium bayonet base.
This is a standard, commonly used replacement bulb. National #800-102. Carefully wipe lamp to insure it is
clean and free of all fingerprints. Replace field lens housing assembly.
b. Changing LED bulb on Models 131-CLED & 132-CLED
To open the illuminators field lens housing, use 0.9mm “L” hex key wrench supplied with your microscope.
Loosen hex screws on lens housing. Remove lens housing to expose LED bulb. Remove bulb by grasping the
plastic base of bulb and gently pulling straight up. Insert new LED bulb, replace lens housing and tighten hex
screws to secure lens housing in place.
c. Replacement of fuse on Models 131-CLED & 132-CLED
The fuse is located at the rear right side of microscope base. To remove fuse from holder, insert a 6mm
screwdriver blade into slot located in rear of fuse holder cap. Slightly depress and rotate screwdriver ¼ turn in
direction of arrow, release pressure on screwdriver to release fuse. Pull cap and fuse out of fuse holder. Insert
proper fuse into fuse cap. Insert fuse cap into fuse holder. Using screwdriver, rotate fuse cap assembly in
opposite direction of arrow until slot engages, depress fuse cap and rotate ¼ turn to lock into fuse holder.