Extech Instruments 380950 User Manual

380950 V1.0 6/07 6
Auto/Manual Ranging
The meter turns on in Autoranging mode. Press the RANGE button to enter manual
ranging. Each press of the range button will step to the next range as indicated by the units
and decimal point location. Press and hold the RANGE button for two seconds to return to
Autoranging mode.
Note: Manual ranging does not function in AC Current or Diode and Continuity check
functions. In Temperature function, it will change the resolution from 0.1° to 1°.
Data Hold
To freeze the LCD meter reading, press the HOLD button. While data hold is active, the
HOLD display icon appears on the LCD. Press the HOLD button again to return to normal
operation.
Backlight
Press and hold the HOLD button for >2 seconds to turn the backlight on/off.
Note: The HOLD feature will activate when the backlight is turned on. Press the HOLD
button again to exit the Hold feature.
Zero Button
Zeros Capacitance and DC Current measurements. Also allows the user to offset the
meter by using the displayed value as the zero reference value. Press the ZERO key
momentarily to activate and to exit Zero mode.

Extech Instruments 380950 Specifications

General

Model	380950
Frequency Response (Sound Level)	31.5Hz to 8kHz
Battery	9V
Display	LCD
Max Voltage	600V
Max Current	400A
Weighting Networks	A & C
Time Weighting	Fast/Slow

Summary

Safety

International Safety Symbols

Indicates user must refer to manual for further information or hazardous voltages may be present.

Safety Notes

Important precautions such as not exceeding input ranges or switching off the meter when not in use.

Warnings

Crucial warnings regarding function switch use, voltage limits, and test lead disconnection.

Cautions

Precautions for preventing damage, shock, injury, or death, including care with high voltages.

Operation

DC/AC Current Measurements

Instructions for measuring AC/DC current using the clamp meter, including zeroing the display.

DC/AC Voltage Measurements

Steps for measuring AC/DC voltage, including connecting test leads and selecting AC/DC mode.

Resistance Measurements

Procedure for measuring resistance, involving test probes and circuit disconnection for accuracy.

Continuity Check

How to perform a continuity check using the meter, noting the audible signal for low resistance.

Diode Test

Procedure for testing diodes, including forward and reverse voltage readings.

Capacitance Measurements

Steps for measuring capacitance, emphasizing safety by discharging capacitors first.

Frequency or % Duty Cycle Measurements

How to measure frequency and duty cycle using the Hz/% function.

Analog Signal Output

Details on using the analog signal output for DCA and ACA ranges with external devices.

Auto/Manual Ranging

Explanation of how to switch between autoranging and manual ranging modes.

Data Hold

Instructions on how to freeze the displayed reading using the HOLD button.

Backlight

How to turn the LCD backlight on and off using the HOLD button.

Zero Button

Information on using the ZERO button for Capacitance and DC Current measurements.

Specifications

PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORIES

OVERVOLTAGE CATEGORY I

Equipment connected to circuits with transient overvoltages limited to low levels.

OVERVOLTAGE CATEGORY II

Energy-consuming equipment supplied from fixed installations.

OVERVOLTAGE CATEGORY III

Equipment in fixed installations, like switches and industrial devices.

OVERVOLTAGE CATEGORY IV

Equipment used at the origin of an installation, like electricity meters.

Maintenance

Cleaning and Storage

Guidelines for cleaning the meter with mild detergent and storing it properly.

Battery Replacement

Step-by-step instructions for replacing the meter's batteries.

Warranty

Calibration and Repair Services