Test Products International 183A - Manual (Page 13)

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F. MAINTENANCE
1. Testing Fuses In Circuit: Both the A and mAµA input
jacks are fuse protected. The fuses can be tested
without removing them from the instrument as
follows:
a. Set the 183A to the diode test function.
b. Insert the red test lead into the V input jack.
c. Touch the tip of the red test lead into the A
input jack making sure you contact the metal.
d. If the display reads any number, the fuse is good.
If the display reads .OL, the fuse is open and
must be replaced.
e. Repeat the same procedure for the uAmA input
jack.
2. Fuse Replacement: Both the A and mAµA input jacks
are fuse protected. If either do not function, replace
fuse as follows:
a. Disconnect and remove all test leads from live
circuits and from the 183A.
b. Remove 183A from protective boot.
c. Remove the three screws from the lower back of
housing holding the compartment cover in place.
d. Remove the compartment cover.
e. Remove the old fuse(s) and replace it with new
fuse(s).
f. Reassemble the instrument in reverse order
from above.
k. RECORD MODE
The record mode saves minimum (MIN) and maximum
(MAX) values measured for a series of reading. Activate
the function as follows:
1. Depress the REC button on the 183A.
2. The 183A will immediately start to record
MIN/MAX values. REC will be on the LCD to
show record mode has been activated. The
reading on the LCD will be the actual reading.
The 183A will give a confirmation beep every
time a new value is recorded.
3. Press the REC button a second time and the
MIN reading will be displayed.
4. Press the REC button a third time and the MAX
reading will be displayed on the LCD.
5. To terminate the record mode, hold the REC
button down for approximately 2 seconds or
turn the rotary switch to a different function.
l. RELATIVE MODE
The Relative mode compares readings to a known value
and displays it as a difference to that value on the LCD.
1. Measure the known value on the 183A and
press the REL button, the LCD will display
zero.
2. Measure next device for comparison.
3. The LCD will display the difference between the
new device and the stored reference value.
5. To terminate the Relative mode, hold the REL
button down for approximately 2 seconds or
turn the rotary switch to a different function.