Operator`s manual

23 Signametrics

equired at least once every

ay to meet the SM2040 accuracy specifications. We recommend that you also perform this function whenever the

p in mind that this is not

substitute for periodic calibration, which must be performed with external standards.

racterizes both the

ternal DMM circuitry as well as the probe cables. To perform OpenCal, attach the probe cables to the DMM,

ces

ources Panel: There are three function buttons in the Source group (SM2044 only). The V, I, LEAK buttons

select one of three source functions, Voltage (DC and AC), IDC and Leakage. The Sources Panel is automatically

enabled when one of the source functions is enabled. It can also be invoked using the Sources Panel selection

under the

application due to the uncertainty of the DMM range, as well as the extra time for range changes. Locking a ran

is highly recommended when operating in an automated test system, especially to speed up measurements. Another

reason to lock a range is to control the input impedance in DCV. The 330 mV and 3.3 V ranges have virtually

infinite input impedance, while the 33 V and 330 V ranges have 10 MΩ input impedance.

S_Cal: This function is the System Calibration that corrects for internal gain, scale factor and zero errors. The

DMM does this by alternatively selecting its local DC reference and a zero input. It is r

external environment changes (e.g. the temperature in your work environment changes by more than 5°C, or the

SM2042, SM2044 on board temperature sensor indicates more than a 5°C change). This function takes less than

few seconds to perform. Disconnect all leads to the DMM before doing this operation. Kee

ClosedLoop: This check box selection is used in conjunction with the AC and DC Voltage-Source functions of th

SM2044. When checked, the DMM monitors the output level and continuously applies corrections to the output

level. When not checked, the DMM is a 12-bit source vs. 16 bits in the ClosedLoop mode.

OpenCal: This check box selection is used in conjunction with inductance measurement. It is necessary to perform

Open Terminal Calibration using this control, prior to measuring inductance. This function cha

leaving the other end of the probe cables open circuited. Then, activate the OpenCal button.

Sync: With this check box selection is active, the DMM measurements are internally synchronized, which redu

the measurement rate, but allows full-scale input swings to be settled in single measurement.

ools menu. This panel allows the entry of values for all of the source functions, including Leakage.

The V-OUT Scroll bar and Text box are used to set

the Voltage for DC and AC Volts as well as for

Leakage. When sourcing ACV, the voltage is in RMS

and the FREQ. Scroll bar and Text box control the

frequency of the source. It is also used to control

inductance frequency. When sourcing DC current, use

the I-OUT set of controls. When measuring timing or

freqeuncy the THRESH set of controls is used for

comperator threshold. All of the source controls are

context sensitive and will be enabled when

riate.