TB 9-6685-319-35
NOTE
The following adjustment procedure applies specifically to
solfront gages, but may be used as a guide for other gages.
Manufacturers' instructions should be used if available.
(1) Deviations either plus or minus by a constant value are corrected by
repositioning the pointer. Remove bezel ring, loosen locking screw (marked L) 1/4 turn, and
adjust screw marked "A". Tighten locking screw and install ,bezel ring.
(2) Deviations varying linearly over range of TI are corrected by repositioning link
screw. Remove protective back or case from mechanism, loosen link screw and move in slot
of sector as required. Tighten link and install protective back of case.
(3) Deviations varying non-linearly over range of TI are corrected by repositioning
arc-loc movement. Remove protective back or case, loosen the three locking screws and
rotate arc-loc movement as required. If indications are first increasingly plus and then
decreasingly plus, rotate arc-loc movement in direction "A". If indications are first
increasingly minus and then decreasingly minus, rotate arc-loc movement in direction "B".
Tighten locking screws.
(4) Repeat (1), (2) or (3) as necessary to obtain indications within tolerance.
9. 0 to 5000 Psi Panel Mounted Hydraulic Gages (1.0 to 20 Percent Accuracy)
a. Performance Check
NOTE
Convert accuracies of TI and standard into pressure units (psi).
If four-to-one accuracy ratio (in pressure units) cannot be
(1) Select a standard pressure gage from pressure gage tester (A2) which will cover
the same range as the TI.
(2) Connect appropriate standard pressure gage and TI in the system in a way that
will ensure that the same pressure will be applied to both gages.
NOTE
The standard pressure gage should be located so that reference
plane of each instrument is the same height to eliminate an
error caused by hydraulic head pressure.
(3) Calculate tolerance limits for TI, using accuracy specified for applicable gage.
(4) Using system pressure source, apply pressure to obtain an indication on
standard pressure gage equal to 10 percent of TI scale.
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