NF FRA51602, Instruction Manual

Page: 162 / 286

5.3 Input settings
5
-
6
FRA 51602
5.3.2 Over-level detection
This function monitors the input signal level for CH1 and CH2 and performs operations such as sounding
the buzzer when the signal exceeds the set level.
■ Setting the over-level detection level
The setting is done using
【
Input
】 –
[OVER DETECT] – [DETECT LEVEL] – [CH1] and – [CH2] . The
maximum setting value is 600 Vrms. The values can be set independently for CH1 and CH2.
When the measurement range (
MEASURE RANGE
) is set to auto-range, over detection is only possible
for the frequency component measured by the instrument. Direct current, impulse noise, and frequency
components other than measurement frequency are not detected. When a fixed range has been set, an
input signal that exceeds the level that can be handled by that range will trigger over-level detection. The
direct component and sudden spike noise will also trigger over-level detection. When measuring in
environments where noise or the DC component are large, set a wide measurement range or use
auto-range.
The over-level state and the non-over-level state are detected when performing measurements with this
instrument. When over-level is detected, the over-level state persists until measurement is performed
again, even if the input level goes to zero.
■ Setting operation for when over-level is detected
When over-level is detected, the over lamp above the CH1 or CH2 input connector on the front panel
lights up. In addition to turning on the lamp, the operations listed below are possible.
• Sounding the buzzer
• Stopping measurement
The setting is done with
【
Input
】 –
[OVER DETECT] – [ACTION] – [BEEP] and – [SWEEP STOP] . If
measurement stop (–
[SWEEP STOP]
) is set to on, over-level detection stops the sweep measurement
and spot measurement. If
【
OSC
】 –
[ON/OFF SYNC] is set to [SYNC] , the oscillator output is turned off
when the measurement is stopped.
Over-level detection level
Operation when over-level
is detected