Tektronix PS 503A, Instruction Manual

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Specification and Performance Check—PS 503A
Performance Check Procedure
1. Check 0-20 Volt Output Voltage
a. Check that all controls on the PS 503A front panel
are fully ccw and that 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
lights may be on; if so, adjust the appropriate CURRENT
LIMIT control cw just enough to turn them off).
b. Set the digital voltmeter to the 2 volts dc range. Use
patch cords to connect the +20 V floating output ter­
minals of the PS 503A to the digital voltmeter input
terminals; connect the 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.
c. Check that the PS 503A + VOLTS controls are fully
ccw and check for a meter reading of .0000, within
±100 mV.
d. Set the digital voltmeter to the 200 volts dc range
and set the PS 503A + VOLTS controls fully cw.
e. Check —for a meter reading of at least +20.1 volts,
but less than +20.4,volts.
f. Adjust the PS 503A + VOLTS controls fully ccw and
move the red patch cord from the 0—20V red binding post
to the 0—20V green binding post on the PS 503A.
g. Repeat parts 1c through 1e, using the PS 503A
— VOLTS controls to check the — 20 V supply.
b. Disconnect the red patch cord from the digital
voltmeter high input terminal and set the digital voltmeter
to the 2000 mA de range. Reconnect the red patch cord to
the digital voltmeter high input terminal.
c. Check— for a current reading of less than 100 mA
for the +20 V supply. The PS 503A + CURRENT LIMIT
light should be on.
d. Move the red patch cord from the PS 503A 0—20V
red binding post to the PS 503A 0—20V green binding
post.
e. Check—for a current reading of less than 100 mA
for the -20 V supply. The PS 503A - CURRENT LIMIT
light should be on.
f. Rotate the PS 503A - CURRENT LIMITcontrol fully
cw.
g. Check— for a current reading of more than
1000 mA, but less than 1500 mA for the —20 V supply.
h. Reconnect the red patch cord to the PS 503A 0—20V
red binding post and rotate the PS 503A + CURRENT
LIMIT control fully cw.
i. Check —for a current reading of more than 1000 mA,
but less than 1500 mA for the +20 V supply.
j. Set all controls on the PS 503A front panel fully ccw
and retain the digital voltmeter connections to the
PS 503A.
h. Set the PS 503A — VOLTS controls fully ccw and
move the red patch cord back to the 0-20V red binding
post on the PS 503A. Check to be certain that all PS 503A
front-panel controls are fully ccw.
2. Check Variable Current Limiting
a. Adjust the PS 503A + VOLTS controls for +5.0 V
output. Move the red patch cord to the PS 503A 0—20V
green binding post and adjust the PS 503A — VOLTS
controls for —5.0 V output. Move the red patch cord back
to the PS 503A 0—20V red binding post.
3. Check Load Regulation
a. Disconnect the red patch cord from the digital
voltmeter input terminal and set the digital voltmeter to the
20 volts dc range. Reconnect the red patch cord to the
digital voltmeter high input terminal; the meter reading
should indicate approximately zero volts. Both CURRENT
LIMIT lights on the PS 503A front panel should be off and
remain off during the load regulation check.
b. Rotate the CURRENT LIMIT
control on the PS 503A
fully cw.
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