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7
TROUBLESHOOTING
PROBLEM
REASON FOR PROBLEM
SOLUTION
Light fails to operate.
Outlet inoperative.
Have qualified service technician
repair outlet.
AC power cord not connected.
Plug into outlet.
Lamp burned out.
Replace lamp.
(131/132-CLED only)
LED bulb burned out.
Replace LED.
(131/132-CLED only)
Fuse blown.
Replace fuse.
Image does not remain in focus
Stage of microscope drops from
its own weight.
Adjust tension control.
Image will not focus
Rack stop not set at proper
position.
Adjust rack stop.
Slide upside down.
Place slide on stage with cover
slip up.
Slide cover slip too thick.
Use 0.17mm thick cover slip
(No.1 cover slip)
Poor resolution
(image not sharp)
Objective lenses dirty.
Clean objective lenses.
Eyepiece lens dirty.
Clean eyepiece lenses.
Too much light.
Adjust disc diaphragm.
Spots in field of view.
Eyepiece or condenser lens dirty. Clean lens. ***
Specimen slide dirty.
Clean slide.
***Spots in field of view can also result from dirt on inside of eyepiece. It is recommended that you have
service technician clean inside of lens.
OPTIONAL ACCESSORIES AND PARTS:
#610-045R
WF10x eyepiece w/reticle, 10mm/100div.
#615-045
WF15x eyepiece w/pointer
#760-045
DIN 60xR objective lens, N.A. 0.90
#800-001
Replacement LED bulb
(131-CLED & 132-CLED only)
#800-102
Replacement bulb, 115v 20 watt tungsten D.C. medium base
(131 & 132 only)
#801-160
Replacement fuse, 0.5 amp, time delay
(131-CLED & 132-CLED only)
#910
Graduated mechanical stage, side mount adjustments (installed by end user)
#951
Dustcover, 16” tall x 13”, heavy vinyl with stitched seams.
#975-001
Carrying case, anodized aluminum, fabric lining, accessory pockets, Velcro straps, keyed lock. Fits all
models in series, except dual head models.
#975-002
Carrying case, anodized aluminum, fabric lining, accessory pockets, Velcro straps, keyed lock. Fits dual
head models.
#975-138
Carrying case, heavy plastic w/foam liner. Fits all models in series, except dual head models.
LIMITED LIFETIME WARRANTY
Please see our website,
www.nationaloptical.com
, for complete warranty details and exclusions.
(Revised 6/24/14)