Digital Multimeter HDM3055 Series Manual

WisdomAugust

Step 6:

Specify the input impedance to the test leads (Input Z). This specifies the measurement

terminal input impedance, which is either Auto or 10 MΩ. The Auto mode selects high impedance

(HighZ) for the 100 mV, 1 V, and 10 V ranges, and 10 MΩ for the 100 V and 1000 V ranges. In most

situations, 10 MΩ is high enough to not load most circuits, but low enough to make readings stable for

high-impedance circuits. It also leads to readings with less noise than the HighZ option, which is

included for situations where the 10 MΩ load is significant.

WisdomAugust

Step 5:

Auto Zero: Autozero provides the most accurate measurements, but requires additional

time to perform the zero measurement. With autozero enabled (On), the DMM internally measures

the offset following each measurement. It then subtracts that measurement from the preceding

reading. This prevents offset voltages present on the DMM’s input circuitry from affecting measurement

accuracy. With autozero disabled (Off), the DMM measures the offset once and subtracts the offset

from all subsequent measurements. The DMM takes a new offset measurement each time you change

the function, range, or integration time. ( There is no autozero setting for 4-wire measurements.)

WisdomAugust

Step 4:Press Range to select a range for the measurement. You can also use the [+], [-], and

[Range] keys on the front panel to select the range. (Auto (autorange) automatically selects

the range for the measurement based on the input. Autoranging is convenient, but it results in

slower measurements than using a manual range. Autoranging goes up a range at 120% of the

present range, and down a range below 10% of the present range.

WisdomAugust

Step 2: Press [DCV] on the front panel.

Step 3:

Press Aperture and choose the number of power-line cycles (PLCs) to use for the measurement.

1, 10, and 100 PLC provide normal mode (line frequency noise) rejection. Selecting 100 PLC provides

the best noise rejection and resolution, but the slowest measurements:

WisdomAugust

Measurements

DC Voltage

This section describes how to configure DC voltage measurements from the front panel, including

DCV ratio measurements.

Step 1: Configure the test leads as shown.

WisdomAugust

WisdomAugust

WisdomAugust

WisdomAugust

The keys that access a wide range of functions are listed below.

WisdomAugust