simpson 444 Micro-Ohmmeter
High accuracy and a high resolution 4-1/2 digitLCD display make the 444 perfect for testing conductive coatings,high power fuses, and antenna grounding systems. With a testvoltage of only 100uV, the 444 will not "punch through"contamination or corrosion. The 444 comes with a test lead with aBNC connector on one end and a Kelvin clip on the other, manual,line cord and Ni-Cad battery for field use.
- AC pulse or DC polarity switching measurementmethods
- Measures from 1 micro-ohm to 20 ohms
- AC lined-powered or battery-powered for lab orfield use
- User-adjustable, low-resistance alarm
Measures from 1 Micro-Ohm to 20 Ohms
Simpson’s high precision Model 444 Micro-Ohmmeter measures resistance from 1
micro-ohm to 20 ohms. It measures using an extremely small test voltage (100 microvolt maximum) and a four wire measurement technique. The resistance reading is indicated on a 4- 1/2 digit LCD display using one of two measuring
modes: An automatic AC measurement mode or a manual DC measurement mode.By limiting the test voltage of the Model 444 to only 100 micro volts the
instrument will not "punch through" contamination or corrosion. An audible tone can be used to indicate resistance values below any selected reading. The Model 444 is powered by either a 120 or 240 AC source or, from self-contained
rechargeable Ni-Cad batteries for field use.
20,000 Count 4 1/2-Digit LCD
Specifications (Continued)
2 Measurement Methods: AC Pulse and DC Polarity Switching
Relative Humidity: 90% maximum up to 35°C,
70% maximum up to +50°C (non-condensing)
8"Punch-Through" Prevention by 100 _V Max.Test Voltage
Temperature Coefficient: 0.1 times the applicable accuracy specification per
°C (0° to 18°C and 28° to 50°C)
User-Adjustable, Low-Resistance Alarm
BatteryVoltageEffect: Plus orMinus (0.15% of input); Fully charged to "B"
AC Test Mode Cancels Offset Voltages and Thermocouple Effects
annunciator displayed
Includes Ni-Cad Battery for Field Use and Test Leads
BatteryLife:8 hourstypical
Specifications
Rated Circuit-To-Ground Voltage: 30V (RMS)
Range
Resolution
Maximum Test Current
Dimensions: 2.7" x 8.4" x 9.0" (68 x 213 x 228 mm) nominal
20mΩ
1μΩ
5mA
200mΩ
10μΩ
500μA
2Ω
100μΩ
50μA
20Ω
1mΩ
5μA
Weight: Approximately 3 Ibs.
 Simpson 444 Micro-Ohmmeter |
