Description
The MPK-257 digital very low resistance ohmmeter is a portable, microprocessor-controlled instrument used to accurately measure resistances of switches and circuit breaker contacts, transformer and motor windings, wire and cable samples, joints in busbars, etc., using test currents from 1mA up to 10 A.
It uses the Kelvin-type, four-terminals measurement principle, thus eliminating errors caused by lead and contact resistances.
Resistance readings are shown in the alphanumeric display with up to a 4½ digit-resolution. It allows to measure resistances of up to 2,000 Ω, with a resolution down to 0.1 µΩ.
Measurements accuracy is guaranteed by the state-of-the-art system for signal amplification, offset-free and with long-term stability.The equipment has a USB interface that allows to download the measured values to a computer for their later analysis.
The open circuit output voltage is of up to 10 V, depending on the selected test current, reducing the stabilization time for the test current when highly inductive elements are measured.
The measurement circuit has an effective protection against voltage peaks originated by those inductances.
Operation is very simple: Just connect the leads, switch-on the equipment, select the test current and press the start button. After a few seconds (depending on inductance of the element), direct reading appears on the display with the measure unit indication (Ω, mΩ or µΩ). If it is necessary, the display will show messages to help the operator (Low battery, Over range, etc).
The equipment is housed in a rugged plastic case with a hinged lid and carrying handle. It is a portable, strong, impact resistant and lightweight equipment, suitable to be used in field, under severe weather conditions. It supplies very reliable and accurate measurements both in laboratory and out in the field.
Technical specifications
Test currents
1 mA - 10 mA - 100 mA - 1 A - 5 A - 10 A.
Each current may be continuously adjustable from 0 to 100 %.
Resistance ranges
0-200 mΩ @ 10 A.
0-1000 mΩ @ 5 A.
0-200 mΩ @ 1 A.
0-2000 mΩ @ 100 mA.
0-20 Ω @ 10 mA.
0-2000 Ω @ 1 mA.
Resolution
0.1 μΩ @ 10 A.
Output voltage
Up to 10 VDC (open circuit) @ 1 A.
Measurement principle
Four-terminal, Kelvin-type.
Basic accuracy
±(0.10% of reading + 3 ULSD*).
*Units of the Least Significant Digit
Advanced features
Digital direct reading of very low resistances in the alphanumerical display, with up to 4½ digits Very fast and accurate measurements.
Serial data output
USB.
Environmental protection
IP65 (with closed lid).
Safety class
Meets the requirements of IEC 61010-1.
Power supply
Rechargeable LFP battery 12 V, 6000 mAh or 100 - 240 V~ mains supply.
Built-in battery charger
For 100 - 240 V~ mains supply or auxiliary 12 V supply input.
Operating temperature range
14 °F to 122 °F (-10 °C to 50 °C).
Storage temperature range
-13 °F to 158 °F (-25 °C to 70 °C).
Humidity range
95 % RH (non condensing).
Equipment weight
Approx. 14.33 lb (6.5 kg).
Dimensions
14.88" x 12.13" x 6.89" (378 x 308 x 175 mm).