Fluke 45 - Manual (Page 32)

Operating the Meter From the Front Panel
Selecting a Measurement Function
3
3-5
Table 3-1. Input Limits
FUNCTION INPUT TERMINALS MAXIMUM INPUT
| V eG and COM 1000V dc
{ and FREQ V eG and COM 750V ac rms, 1000V peak, 2 x 10 7 V-Hz
normal mode, or 1 x 10
6
V-Hz common
mode (whichever is less)
mA D and FREQ 100 mA and COM 300 mA dc or ac rms
\ and FREQ 10A and COM 10A dc or ac rms (or 20A dc or ac rms for
30 sec. Max)
e V eG and COM 500V dc or ac rms on all ranges
G V eG and COM 500V dc or ac rms
All Functions Any terminal to earth 1000V dc or peak ac
Selecting a Measurement Function
Press a function button (white), shown in Figure 3-5, to select a measurement function To
select ac + dc total rms readings, press
Z and Y, or D and C, simultaneously.
When you select a function, annunciators turn on to indicate the function selected. If a
reading is shown on the secondary display when a function button is pressed, the
secondary display will be turned off.
Ranges and full scale values are summarized in Table 3-2 for voltage, Table 3-3 for
current, Table 3-4 for ohms, and Table 3-5 for frequency.
Ranging
(
E, U, T)
Ranging operations are performed using the
E, U, and T buttons (see Figure 3-6).
Autoranging
When you are in the autorange mode, the AUTO annunciator is lit.
In autorange, the meter automatically selects the next higher range when a reading is
greater than full scale. If no higher range is available, "OL" (overload) is displayed on the
primary or secondary display. The meter automatically selects a lower range when a read-
ing is less than approximately 9 % of full scale.