FINE INSTRUMENTS CORPORATION FINEST 135, User Manual

5.6 Measuring Frequency

To enable 

 frequency measurement mode, press the Hz

pushbutton. This Meter displays Hz, DUAL, and AUTO. The
frequency of the current flow is displayed. AUTO (auto-
ranging)   applied   the bar graph, 

 represents rms

value of the current flow. When in AUTO, frequency 
surement uses an auto trigger threshold based on one-half
of the peak current measurement. This provides the best 
sitivity and noise immunity.

To select a fixed 40A or 400A bar graph display (AUTO 

no longer displayed), press the RANGE pushbutton. With a
fixed 40A or 400A scale, fixed trigger thresholds are 
for frequency readings. The thresholds are 

 (40A scale)

or 40A (400A scale). The frequency display   

 when

a trigger threshold is not reached.

Press the RANGE pushbutton for 2 seconds and then release
in 

   return   autoranging mode. This Meter 

ledges with a beep 

 and displays AUTO on the digital

display. Press the other 

 (A or V or   or 

l 

II)   

button   exit the frequency mode.

5.7 Using Data Hold

When HOLD   used while measuring frequency, RANGE

 be 

only for imposing trigger thresholds of 6A

on the 40A 

scale, 

and 40A on the 400A scale. The 

cy reading will be 

 when HOLD   released, if the 

ger threshold is not reached.

When in the HOLD mode, 

 Meter 

 be

 from the held 

   one of the other 

when HOLD is automatically released.

Press the HOLD pushbutton again   

 is no longer

displayed) in 

   exit HOLD.

Press the RANGE pushbutton for 2 seconds and then release
in 

   autoranging mode. This Meter acknowledges with

a beep 

 and displays AUTO on the digital display.

5.8 Measuring 

 Voltage

Press the V pushbutton   enable the voltage measurement
mode and then select AC or DC by toggling the AC DC 
button. This Meter defaults in the autoranging mode and
displays   AC and AUTO. AUTO (autoranging) is applied

 the bar graph.

To measure voltage, connect this Meter in parallel with the

load or circuit 

 of the three 

 voltage

 presents an input impedance of approximately 10 

in parallel with less than 100 pF.

Measurement errors due to circuit loading 

 when

making either AC or DC voltage measurement on circuits with
high 

 impedance. In most 

 the error is 

ble (0.1% or 

 if the measurement circuit 

   10 Kilohms or 

To freeze the digital display reading (HOLD   not applied

 the bar graph.), press the HOLD pushbutton.

displayed when HOLD is enabled.

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