Martindale MM68 True RMS Digital Multimeter

Includes: Martindale MM68, Test Leads, Spare 0.5A/500V Fuse, 9V Battery (Installed), Instruction Manual.

Reference MARMM68

Brand Martindale Electric

The Martindale MM68 is a 4½ digit, true RMS Digital Multimeter with a 22 segment analogue bar graph. It can measure AC voltage up to 750V, DC voltage up to 1000V all displayed on its LCD screen.

Other functions of the MM68 include frequency, capacitance, resistance, diode test and an audible continuity test. It also has an auto-power off feature and on-screen low battery indication.

The MM68 will auto power off after approximately 30 minutes. Pressing any button will turn the MM68 back on.

FEATURES

True rms AC voltage to 750V.
DC voltage to 1000V.
True rms AC current to 10A.
DC current to 10A.
Resistance to 220MΩ.
Capacitance to 22mF.
Frequency to 22MHz.
Continuity with audible indication.
Diode testing.
Duty cycle.
Max/Min indication.
Auto power off.
Display backlight.
Relative function.
Auto ranging.
Incorrect connection warning.

Martindale DMM Comparison Chart

MODEL	MM65	MM68	MM94
AC/DC Voltage	✔	✔	✔
AC/DC Current	✔	✔	✔
Resistance / Continuity	✔	✔	✔
Diode test	✔	✔	✔
Frequency		✔	✔
Capacitance		✔	✔
True RMS		✔	✔
Auto-ranging	✔	✔	✔
Backlight		✔	✔
Overmoulded Holster	✔	✔	✔
Other		Min/Max Duty Cycle	Min/Max/Peak Temperature Duty Cycle Low Pass Filter
Safety rating	CAT III 600V	CAT III 600V	CAT IV 600V

Martindale MM68 True RMS Digital Multimeter Specifications

Specified Accuracy	All specified accuracies are at 23°C ± 5°C <75% RH for 1 year.
Temperature Coefficient	0.1 x (specified accuracy) per °C (0 to 18°C, 28 to 50°C).
DC Volts
Ranges	220mV, 2.2V, 22V, 220V, 1000V.
Resolution	0.01mV, 0.0001V, 0.001V, 0.01V, 0.1 V.
Accuracy	± (0.05% of rdg + 5 dgts).
Input Impedance	220mV: >100MΩ; 2.2V: 10 MΩ; 22V to 1000V: 9.1MΩ.
Overload Protection	1000V DC or 750 AC rms.
True RMS AC Volts
Ranges	220mV, 2.2V, 22V, 220V, 750V.
Resolution	0.01mV, 0.0001V, 0.001V, 0.01V, 0.1V.
Accuracy	220mV range (50 Hz to 500 Hz) ± (1.2% of rdg + 10 dgts) 2.2V to 220V ranges (50 Hz to 500 Hz) ± (1.2% of rdg + 10 dgts) (500 Hz to 2 kHz) ± (2.0% of rdg + 20 dgts) 750V range (50 Hz to 500 Hz) ± (2.0% of rdg + 20 dgts) AC coupled true rms specified from 5% to 100% of range.
Crest Factor	≤ 3.
Input Impedance	220mV: >100MΩ; 2.2V: 10MΩ; 22V to 750V: 9.1MΩ.
Overload Protection	1000V DC or 750 AC rms.
DC Current
Ranges	220μA, 2200μA, 22mA, 220mA, 10A *
Resolution	0.01μA, 0.1μA, 0.001mA, 0.01mA, 0.001A.
Accuracy	220μA to 22mA ranges ± (0.5% of rdg + 10 dgts) 220mA range ± (1.0% of rdg + 10 dgts) 10A range ± (2.0% of rdg + 10 dgts) * Current on 10 A range applied for 60 seconds max followed by a 10 minute cooling period.
Input Protection	0.5A/500V fast blow ceramic fuse 10A/500V fast blow ceramic fuse.
True RMS AC Current
Ranges	220μA, 2200μA, 22mA, 220mA, 10A *
Resolution	0.01μA, 0.1μA, 0.001mA, 0.01mA, 0.001 A.
Accuracy	220μA to 220mA (50 Hz to 1 kHz) ± (1.5% of rdg + 5 dgts) 10A range (50 Hz to 1 kHz) ± (2.5% of rdg + 5 dgts) * Current on 10 A range applied for 60 seconds max followed by a 10 minute cooling period AC coupled true rms specified from 5% to 100% of range.
Crest Factor	≤ 3.
Input Protection	0.5A/500V fast blow ceramic fuse 10A/500V fast blow ceramic fuse.
Resistance
Ranges	220Ω, 2.2kΩ, 22kΩ, 220kΩ, 2.2MΩ, 22MΩ, 220MΩ.
Resolution	0.01Ω, 0.0001kΩ, 0.001kΩ, 0.01kΩ, 0.0001MΩ, 0.001MΩ, 0.1MΩ.
Accuracy	220Ω to 220kΩ ranges ± (0.5% of rdg + 10 dgts) 2.2MΩ range ± (1.0% of rdg + 10 dgts) 22MΩ range± (2.0% of rdg + 10 dgts) 220MΩ range± (5.0% of rdg + 10 dgts).
Open Circuit Voltage	-0.45 V DC (-1.2 V DC on 220 Ω range).
Overload Protection	500 V DC or AC rms.
Capacitance
Ranges	22nF, 220nF, 2.2μF, 22μF, 220μF, 2.2mF, 22mF.
Resolution	0.001nF, 0.01nF, 0.0001μF, 0.001μF, 0.01μF, 0.0001mF, 0.001mF.
Accuracy	22nF range ± (3.0% of rdg + 80 dgts) 220nF to 220μF ranges ± (3.0% of rdg + 5 dgts) 2.2mF to 22mF range ± (5.0% of rdg + 20 dgts).
Overload Protection	500 V DC or AC rms.
Frequency
Ranges	22Hz, 220Hz, 22kHz, 220kHz, 2.2MHz, 22MHz.
Resolution	0.01Hz, 0.1Hz, 0.001kHz, 0.01kHz, 0.0001MHz, 0.001MHz.
Accuracy	± (0.1% of rdg + 3 dgts).
Input Sensitivity	2Hz ~ 2.2MHz: >2.5Vrms. 2.2MHz ~ 22MHz: >2.5Vrms and <5Vrms.
Minimum Input	22Hz range > 2Hz. 220Hz range > 20Hz.
Minimum Pulse Width	> 25ns.
Duty Cycle Limits	> 30% and < 70%.
Overload Protection	500VDC or AC rms.
Duty Cycle
Range	10% to 95%
Resolution	0.01%
Pulse Width	>10us.
Frequency Range	10% to 95% (40Hz to 20kHz).
Accuracy	(5V logic) ± (2.0% rdg + 5 dgts).
Overload Protection	500V DC or AC rms.
Continuity
Audible Indication	< 30Ω.
Response Time	500ms.
Overload Protection	500V DC or AC rms.
Diode Test
Test Current	1.2mA Approx.
Resolution	0.1mV.
Accuracy	±(2%rdg + 5 digits).
Audible Indication	<0.25V.
Open Circuit Voltage	3.0V DC typical.
Overload Protection	500V DC or AC rms.
General Specifications
Display	4½ digit liquid crystal display with a maximum reading of 22000.
Analog bargraph	22 segments with measurement 20 times per second.
Polarity	Automatic, positive implied, negative polarity indication.
Overrange	(OL) or (-OL) is displayed.
Power	Single standard 9 volt battery, NEDA 1604, JIS006P, IEC 6F22.
Dimensions	165mm (H) x 78mm (W) x 42.5mm (D).
Weight	Approx. 285g.
Martindale MM68 warranty	Two-years.