Light source
Figure 2-14. Viewing the Indicating Fiber Moving Away From Zero
Step 1. Remove the dosimeter from the charging pedestal and observe the reading on the
dosimeter's calibrated scale.
Step 2. If the indicating fiber can still be seen to move, clean the charging end of the dosimeter.
Then repeat the procedure. If leakage still is evident after the second charging, the dosimeter is faulty.
Step 3. If leakage is evident when the dosimeter is installed in the charger but not when it is
removed, clean the charging pedestal thoroughly. Then repeat the procedures for charging the dosimeter.
Step 4. If leakage still is evident when the dosimeter is in the charger but not when it is removed,
the charger is faulty. However, the charger can still be used if it will charge a dosimeter below zero. If
leakage is evident only when the dosimeter is in the charger, proceed as follows:
(a) Install the dosimeter in the charger. Press down firmly on the dosimeter.
(b) Turn the charging knob clockwise until the indicating fiber is off-scale left of zero.
(c) Watch the indicating fiber closely. Remove the dosimeter from the charger the instant the
indicating fiber reaches zero on the calibrated scale.
(d) If necessary, repeat Steps 4(a) through 4(c) until a zero reading is obtained after removing
the dosimeter from the charger.
d. Capacitive-jump-occurrence procedures. On some dosimeters, particularly low-range
instruments, an instantaneous partial discharge may occur as the dosimeter is removed from the charger.
This partial discharge is called a capacitive jump. After the dosimeter has been charged, remove the
dosimeter from the charging pedestal. Then observe the reading on the calibrated scale. If the indicating
fiber has jumped upscale, proceed as follows:
Step 1. Place the charging end of the dosimeter over the charging pedestal. Turn the charging
knob clockwise until the indicating fiber is on the downscale side of zero an amount equal to the
capacitive jump.
CM2306
2-12
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