Tektronix PS 503A, Instruction Manual

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Adjustment —PS 503A
1. Adjust
20 Volt Output Voltages
a. Check —that all controls on the PS 503A front panel
are fully ccw and the 400 mA MAX indicator light is off
(this light should remain off as long as the PS 503A is
installed in the high-power compartment of the power
module). Also check that both CURRENT LIMIT indicator
lights are off. (For instruments SN B022064-below, these
iights may be on; if so, rotate the appropriate CURRENT
LIMIT control cw just enough to turn them off).
b. Set the digital voltmeter to the 2 volts dc range and
check for a meter reading of zero volts, ±100 mV.
c. Set the digital voltmeter to the 200 volts dc range.
Use patch cords to connect the plus 20 V floating output
terminals of the PS 503A to the digital voltmeter input
terminals; red patch cord from the 0—20V red binding post
to the digital voltmeter high input terminal, and the black
patch cord from the COMMON (black) binding post to the
digital voltmeter low input terminal.
d. Turn the PS 503A +VOLTS fine and coarse controls
fully cw.
e. Adjust—R45, +20 Adj, for a meter reading of +20.2
volts, ±0.1 volt. See Fig. 3-1 for adjustment location.
f. Adjust the PS 503A + VOLTS fine and coarse
controls fully ccw and move the red patch cord from the
0— 20V red binding post to the 0 — 20V green binding post.
g. Turn the PS 503A — VOLTS fine and coarse controls
fully cw.
h. Adjust —R145, —20 Adj, for a meter reading of—20.2
volts, ±0.1 volt. See Fig. 3-1 for adjustment location.
i. Adjust the PS 503A — VOLTS fine and coarse
controls fully ccw.
j. This completes the adjustment portion of this
procedure. However, to verify satisfactory performance
after adjustment, perform the complete Performance
Check procedure as specified in Section 2 of this manual.
3-2
REV. A, AUG. 1977