Getting Started
Connecting th
eAmplifier to an Oscilloscope
You will need an oscilloscope to display the TCPA300 and TCPA400 measurement
output. To use the full dynamic range of the probe/amplifier combination, the
oscilloscop
e must be capable of displaying a vertical scale factor of 1 mV/div to
1 V/div.
If you are us
ing a TEKPROBE II-compatible oscilloscope, use the
TEKPROBE-to- TEKPROBE interface cable. Otherwise, use the supplied
50 Ω BNC cable to connect the amplifier OUTPUT connector to your oscilloscope.
(SeeFigure1onpage1.)
The input impedance of the oscilloscope channel must be 50 Ω, or you will
encounter slowed pulse response, increased aberrations, or incorrect DC
measurement amplitudes. If your oscilloscope provides only 1 M Ω inputs, you
need to attach a 50 Ω feed-through termination between the o scilloscope input
and the B
NC cable. Do not install this termination at the amplifier end of the
BNC cable.
To util
ize the full bandwidth capability of the TCPA300 and TCPA400 and
attached current probe, the oscilloscope bandwidth must be approximately five
times that of the current probe. For example, when using a TCP312A Current
Probe, the oscilloscope bandwidth must be at least 500 MHz. When using a
TCP305A Current Probe, the oscilloscope bandwidth must be at least 250 MHz.
After you have connected the amplifier to the oscilloscope, allow the equipment
to warm up to a stable temperature; usually 20 minutes is required.
Pow
er on the Amplifier
Connect the power cord to the power input connector on the rear of the amplifier,
and then connect the power cord to your local mains supply (100 VAC to
2
40 VAC, 50 Hz to 400 Hz). To allow for proper ventilation, place the rear panel
of the amplifier at least 2 inches away from any obstructions. Set the amplifier on
the bottom rubber feet, and keep papers and other items away from the bottom of
the amplifier which could restrict airflow and cause overheating.
Power on the amplifier by pressing the ON/STANDBY button at the lower-left
corner of the front panel. The amplifier goes through a self-test and cycles the
front-panel LEDs.
NOTE. The amplifier stores the power state it is in when the power cord is
unplugged. If you do not put the amplifier into STANDBY mode before unplugging
it, the amplifier will power on immediately when you plug it in again.
When you connect a probe to the amplifier, the amplifier uses detection circuitry
to indicate probe conditions such as noncompatible probe type and probe open.
8 TCPA300/400 Amplifiers and TCP300A/400 Series Current Probes User Manual