Tektronix TCPA300 SERIES, Инструкция по эксплуатации

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Control Summary
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TCPA300/400 Amplifiers and TCP300/400 Series Current Probes Instruction Manual
TCPA300 and TCPA400 Controls
These front panel controls and indicators are common to both the TCPA300 and
TCPA400 current probe amplifiers, unless otherwise indicated.
When pressed, this button performs two functions that maximize measurement
accuracy. First, the amplifier generates a degauss signal to remove any residual
magnetism from the attached current probe. Second, the amplifier initiates an
operation to remove any undesired DC offsets from the circuitry. During the
degauss process, the amplifier is busy and cannot be used to measure current.
The indicator light next to the PROBE DEGAUSS AUTOBALANCE button
blinks red whenever the amplifier detects that the current probe needs degaus-
sing. The amplifier cannot detect all circumstances that require probe degaus-
sing, so you may need to degauss the probe at times when the PROBE
DEGAUSS AUTOBALANCE light is not blinking red. The red blinking light
serves as a reminder to degauss the current probe when one of the following
conditions occurs:
H
The amplifier has just been turned on with a current probe connected.
H
The current probe has been changed.
H
An overload was detected.
To perform the probe degauss/autobalance function, remove the probe from all
conductors (or ensure that the conductor under test has no power), make sure the
probe is locked closed, and then press the PROBE DEGAUSS AUTOBA-
LANCE button. The probe degauss/autobalance routine will not pass if the
current probe is disconnected from the amplifier input, or if it is unlocked (the
PROBE OPEN LED is on).
The indicator blinks orange during the time the amplifier is busy performing the
probe degauss functions. When the degauss and autobalance procedure is
complete, the indicator light turns green.
The PROBE DEGAUSS AUTOBALANCE indicator light will be orange if the
MANUAL BALANCE buttons have been pressed after a degauss has been
successfully completed. This indicates that the DC offset value has been
manually changed from the original value set during the degauss routine.
Depending on the amount of offset (balance) you have entered with the
MANUAL BALANCE buttons, another degauss operation may be necessary to
ensure accurate measurements. Generally, if you change the DC offset by more
than 5 divisions, you should de-energize the circuit under test and perform
another degauss routine. Then, re-energize the circuit and take your measure-
ments.
If the degauss operation has failed, and the AC and DC COUPLING LEDs are
alternately flashing, this indicates the amplifier is displaying an error code with
the four status LEDs on the lower-left front panel. If this occurs, refer to
PROBE DEGAUSS
AUTOBALANCE Button
and Indicator