TB 9-6670-258-35
(31) Repeat technique of (17) through (23) above, checking each TI cell from 500 to
1000 pounds in 50 pound increments. Indication on TI and load cell indicator will be
within 25 pounds.
NOTE
If calibration report for load cell does not provide readings for
50 and 200 pound loads, begin at 350 pounds.
b. Adjustments
(1) Connect multimeter to gray (+) and violet (-) terminals of TI power supply switch.
(2) Adjust R201 (fig. 2) for 24 V dc as indicated on multimeter.
(3) Zero adjust TI in a no load condition.
(4) Apply a known load to system, preferably 50,000 pounds.
(5) Set TI INITIAL LOAD switch and WEIGHT dial of indicator to amount of
load applied.
(6) Adjust appropriate TRIM POT (span) (fig. 3) until indicator pointer of TI
indicates a null. A trim pot is provided for each cell. These adjustments are located next to
the terminal strip of the indicator amplifier assembly. (R)
NOTE
In older models of the TI, no span adjustment can be made.
Resistors of the proper value must be installed. If this becomes
necessary, install adjustable resistors of the proper nominal
value and repeat b (3) through (6) above.
(7) After matching errors are obtained, apply loads to any cell in 5000 pound increments.
(8) Remove TI panel.
(9) Remove cover of board and component assembly (fig. 4) for best linearity.
(10) Adjust resistor SPOOL FINGERS (fig. 4). (R)
NOTE
When sliding these fingers, each cell error will shift a similar
value. If cell with highest error value at an applied load is
being adjusted to a lower value, cell with lowest error value
cannot be allowed to drop below the tolerance limits.
(11) Replace board and component cover and TI panel.
(12) Repeat performance test.
a. Deenergize and disconnect all equipment.
b. Annotate and affix DA label/form in accordance with TB 750-25.