Tektronix IsoVu TIVM Series, User Manual

Page: 37 / 82

Operating information
Selecting a sensor tip cable
CAUTION.
Avoid over-voltage conditions that can damage or degrade the sensor
head input termination by selecting the wrong sensor tip cable. The sensor head
SMA input is a 50
Ω terminated input. Selecting the correct sensor tip cable
attenuation factor is crucial to ensure that the sensor head input termination is not
degraded or damaged by an over-voltage condition. Select the sensor tip cable
that will provide the highest attenuation possible for the signal being measured.
This also provides the highest differential impedance to the circuit-under-test.
When selecting a sensor tip cable for a particular application, consider the
following questions:
What is the maximum RMS/Peak Voltage at the test point being measured
(for example, under a fault condition)?
What is the minimum differential loading (input resistance) that my circuit
can tolerate?
How large of a signal do I want to display at one time on the oscilloscope?
What sensitivity do I need (for example, the minimum V/div setting)?
The following table will help you select the correct sensor tip. Start at the top of
the table and work down. Choose the
fi rst tip that meets all of your criteria.
Table 6: Sensor tip selection table
Differential input speci fi cations
Sensor tip
Most sensitive
V/div setting
1
Linear voltage
range
2
Maximum
non-destruct
voltage (RMS) Maximum
non-destruct
voltage (Peak)
Differential input
resistance
IVTIP50X 50 mV/div ±50 V (100 V
p-p
) 35 V
rms
200 Vpk 2.5 k Ω
IVTIP25X 25 mV/div ±25 V (50 V
p-p
) 25 V
rms
107.5 Vpk 1.25 k Ω
IVTIP10X
10 mV/div ±10 V (20 V
p-p
)
16 V
rms
43 Vpk
500 Ω
IVTIP5X
5 mV/div ±5 V (10 V
p-p
)
12 V
rms
21.5 Vpk
250 Ω
IVTIP1X
1 mV/div ±1 V (2 V
p-p
)
3 V
rms
4.3 Vpk
50 Ω
1
On 1X range
2
On 2X range
TIVM Series Measurement System User Manual 19