Tektronix TCPA300 SERIES, Instruction Manual

Page: 153 / 205

TCP303 and TCP404XL Adjustments
TCPA300/400 Amplifiers and TCP300/400 Series Current Probes Instruction Manual
6- 17
1. Move the oscilloscope trace to one graticule line from the bottom of the
screen.
2.
Do not clamp the current probe around any conductor, but make sure the
jaws are locked shut.
3. Remove the probe access plugs for 1 s, 10 s, and DC Gain.
4. Preset the probe adjustments: Refer to Figure 6--5 on page 6--12 for
adjustment locations. Do this only at the beginning of the probe adjustment
process.
a.
Set the 1 s adjustment fully clockwise
b. Set the 10 s adjustment fully counterclockwise
5. Press the amplifier PROBE DEGAUSS AUTOBALANCE button. Wait for
the degauss/autobalance routine to complete before proceeding. The routine
is complete when the PROBE DEGAUSS AUTOBALANCE LED returns to
green.
6.
Lock the jaws of the probe around the built-in current loop on the high
amplitude pulse generator. Observe proper polarity; the arrow-shaped
indicator on the probe points away from the (+) terminal of the current
source.
7.
Repeat steps a through d to achieve optimium response:
a. Adjust the DC Gain adjustment to produce an amplitude of five graticule
divisions (5 amps) at the 100
s portion of the pulse.
b. Adjust the 10 s control for a flat waveform to match the level at the
100 s point.
c. Adjust the oscilloscope sweep to 1 s/div.
d. Adjust the 1 s control to flatten the front end of the pulse.
NOTE
. The 10 s and 1 s adjustments on the TCP404XL interact. Adjusting
them can be a repetitive process. You may need to balance between short and
long term response to meet both specifications at once.
8. Verify the DC Gain Accuracy using the procedure on page 6--18. You may
have to make some minor adjustments to the DC gain adjustment to achieve
the highest accuracy possible.
TCP404XL Procedure