Tektronix TCPA300 SERIES, Instruction Manual

Page: 67 / 205

Troubleshooting and Error Codes
TCPA300/400 Amplifiers and TCP300/400 Series Current Probes Instruction Manual
3- 21
Table 3- 3: Troubleshooting (Cont.)
Problem Remedy
Measurements exhibit excessive noise Current Probe is not locked. Lock the current probe.
Current Probe is improperly connected to the amplifier input.
Amplifier output is not terminated into 50
Ω
load. Set input impedance of oscilloscope
to 50
Ω
or connect a 50
Ω
feed-through termination at the oscilloscope input, not at
the amplifier output.
Defective current probe transformer.
Measurement aberrations exceed the specified
limit The amplifier output is not terminated into 50
Ω
load. Set the input impedance of the
oscilloscope to 50
Ω
or connect a 50
Ω
feedthrough termination (see the replaceable
parts list on page 8--6) at the oscilloscope input. Do not attach the termination to
amplifier output.
The measurement exceeds the maximum continuous current or Ampere-second
product ratings of the Current Probe. (For more information, see
Current Limits on
page 3--4 . ) If possible, upgrade to a probe with a higher current rating or use a CT-4
transformer.
Excessive low frequency droop in pulse
response or low DC gain accuracy Check that the probe slider is fully closed and locked.
Check and clean the probe transformer and lid.
Degauss the probe.
The amplifier or the oscilloscope may be AC coupled. Set the COUPLING to DC.
Measurements exhibit excessive delay or
slowed pulse response The amplifier output is not terminated into 50
Ω
load. Set the input impedance of the
oscilloscope to 50
Ω
or connect a 50
Ω
feedthrough termination (see the replaceable
parts list on page 8--6) at the oscilloscope input. Do not attach the termination to the
amplifier output.
The measurement exceeds the Ampere-second product of the Current Probe. If
possible, upgrade to a probe with a higher current rating or use a CT-4 transformer.
The oscilloscope bandwidth limit is turned on. Verify that the bandwidth limit switch on
the oscilloscope is set to the desired bandwidth position.
Probe jaw not opening and closing freely The jaw mechanism is dirty -- disassemble probe, clean and lubricate. Refer to the
probe disassembly procedures on page 7--13.