NF FRA5087, Instruction Manual

Page: 56 / 194

3.3 Input and output terminals
FRA5087 3-16
3.3 Input and output terminals

Analyzer input terminals (CH1 and CH2)
CH1
CH2
2
A TT
1MΩ
cabinet
1
A TT
1MΩ
Each of the analyzer input terminals of the FRA5087 is electrically insulated from the cabinet, the
oscillator and the other analyzer input terminal. The minimum breakdown voltage is 250 Vrms
(measurement category I) between each of the input and output terminals and the cabinet, between
CH1 and the oscillator, between CH2 and the oscillator and between CH1 and CH2, respectively
when the accompanying insulated coaxial cable is being used. Restriction of 30 Vrms applies
when a cable other than the accompanying cable is used. Note that accidents due to electric
shocks could occur, if the voltages exceeding the minimum breakdown voltage are applied
between the above mentioned insulated parts, leading to dielectric breakdown. Refer to “3.4
Insulation breakdown voltages of input and output voltages” by all means, when you make a
measurement where high voltages are applied between any two of the cabinets, CH1, CH2 and the
oscillator.
WARNING
！
 Do NOT connect to any measurement target that exceeds 250 Vrms of
measurement Category I.
Doing so may result in insulation breakdown, imposing electrical shock.
 You could be suffered from electric shocks when you measure high voltage
circuit signals. Use accessory coaxial cables of the insulation type by all
means, so that you cannot directly touch metallic portions of the BNC
connectors at the analyzer input terminals.
The input terminals have the input impedance of 1 M  (parallel capacitance of 25 pF  5 pF) and
the maximum allowable input voltage of  350 V for AC+DC. Never apply any voltages
exceeding the maximum allowable voltage, since the inside of the instrument will be damaged by
application of voltages exceeding the minimum allowable voltage.
FRA5087 has the capability of measuring the amplitude and the phase of input signals up to 10
MHz. Use the same type and the same length of signal cables to be
connected to individual
channel inputs so that the phase can be measured with high accuracy at high frequencies.
The connection between the input connector and the internal circuits is cut off when the power
supply is off.