Table 3-2. Troubleshooting, Operator - Continued
3. METER NOT OPERATIVE
Step 1. Inspect for a distorted indicating needle.
a. Straighten and unjam.
b. Insure needle is fastened to post.
Inspect condition of meter scales.
a. Discard any found chipped or distorted.
Inspect lamp operation in AC & DC mode.
a. Adjust wavelength dial to 400 nm. Insure light shield is in place. Place meter on AC power
h. Operate the light control - a full scale deflection should be obtained. If not obtained, replace
lamp as follows:
Remove the panel, lay it face down on a protective mat.
from the amplifier board connection BC4 (fig. 4-1).
Loosen the bulb setscrew in the lamp holder and extract
Disconnect the lamp cable
c. If lamp is operating on AC, remove AC source of power, lift out panel from case, lay it in-
Install the replacement lamp assembly in reverse order of removal. The lamp must be
aligned with the lamp filament positioned vertically, and placed as far in the lamp holder
Reassemble the instrument and check alignment by placing a piece of paper in the cell
holder and, with the light switch ON, adjusting the wavelength dial to 550 nm to bring
the bulb filament image into focus on the paper. Proper alignment gives an image of a
vertical, elongated circle completely enclosing the filament image.
The filament image is positioned by rotating the bulb within the lamp holder. Avoid
overtightening the bulb setscrew. Bulb damage could result.
verted on a protective cover, inspect battery. If leakage is visible, discard batteries and clean
up case. Replace batteries from spare set as follows: Be sure polarity is correct.