Version 2.0 1/05
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Introduction
Congratulations on your purchase of Extech’s Model 380580 Battery Powered Milliohm
Meter. This device offers five resistance ranges with resolution as low as 0.1mΩ. The 4-wire
Kelvin clip connection ensures optimum accuracy. Typical applications include transformer,
motor coil, and PC Board resistance measurements. This professional meter, with proper
care, will provide years of safe reliable service.
Specifications
General Specifications
Display 1.0" (25 mm) LCD (1999 counts)
Measurement terminals 4-Terminal Kelvin type
Measurement Range Five ranges (see listing below)
Sampling Time Approximately 3 times per second
Over input indication Indication of "1 - - -"
Operating Temperature 5ºF to 131ºF (-15ºC to 55ºC)
Operating Humidity <80% RH
Power Supply 8 x 1.5V AA Batteries
Weight 3.3 lbs (1.5kg)
Dimensions 9.8x7.5x4.3" (250x190x110 mm) with cover
Range Specifications
Range
Resolution Test
Current
Accuracy Open Circuit
Voltage
200.0mΩ 0.1mΩ 100mA ± 0.5% + 2 digits 4.2V
2000mΩ 1mΩ 100mA ± 0.5% + 2 digits 4.2V
20.00Ω 0.01Ω 10mA ± 0.5% + 2 digits 4.2V
200.0Ω 0.1Ω 10mA ± 0.5% + 2 digits 4.3V
2000Ω 1Ω 1mA ± 0.5% + 2 digits 4.4V
International Symbol s
This symbol, adjacent to another symbol or terminal, indicates the user must
refer to the manual for further information.
This symbol, adjacent to a terminal, indicates that, under normal use,
hazardous voltages may be present
Double insulation
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Meter Description
1. Current Terminals
2. Potential Measurement Terminals
3. LCD Display
4. Start/Stop Test Button
5. Range Select/Power Switch
6. LED Error Lights
• No Test/Over Temperature
• RP Voltage Regulation
• RC Current Regulation
7. Current/Range Table
Leads
Current Leads- Banana plug to alligator clip
C1- Green
C2- Blue
Voltage Potential Leads- Banana plug to alligator clip
P1- Red
P2- Black
Kelvin Clips- Banana Plugs (2) to Kelvin Clip
Red (P1) Green (C1)
Black (P2) and Blue (C2)
Measurement Considerations
1. Do not apply voltage to the meter input terminals. Meter damage may result.
2. Always insure that the circuit to be measured is switched OFF, isolated and
completely de-energized before connecting the test leads.
3. If the Over Temperature LED (NO TEST) indicator is lit, allow the instrument to
cool down before proceeding further.
4. The RC led indicates when the test current falls out of regulation. Selecting a higher
range may eliminate the condition.
5. The RP led indicates when the voltage on the device under test is too high.
Selecting a lower range may eliminate the condition.
6. If either the RC or RP led is on, the measurement may be in error.
7. The current terminals are fuse protected.
8. Keep the potential test leads as short as possible. Long leads may introduce noise.
9. When using the four separate alligator clip leads always place the current leads
outside the potential leads.
