Despite its compact nature, Martindale's ET4 is capable of a lot. It can carry out testing of DC voltage, AC voltage, DC and AC current, frequency, resistance and also performs continuity and diode testing. It can also be used to detect the presence of voltage from 70V to 600V thanks a built-in non-contact voltage detector.
For any practising electricians, having access to all of these functions on one device makes testing as simple as possible. The ET4 can even be used to take simultaneous measurements of current/voltage and frequency/voltage, further speeding up testing.
Test results are shown through a built-in LCD screen on the front of the device and the mode can be easily adjusted by turning a rotary dial on the front of the tester.
Additional functions of the Martindale ET4 include autoranging, a display hold function which freezes the last reading taken and an auto shut down facility which will activate when the tester is left idle.
Electrical
All specified accuracies are at 23°C ± 5°C <75% RH for 1 year.
Temperature Coefficient: <0.1 x (specified accuracy) per °C (0°C to 18°C, 28°C to 40°C)
DC Voltage
Range | Resolution | Input Impedance | Accuracy |
500mV | 0.1mV | 1.1MΩ | ± (0.5% of rdg + 2 dgts) |
5V | 0.001V | 1MΩ | |
50V | 0.01V | ||
500V | 0.1V | ||
600V | 1V |
Overload Protection: 600V DC or AC rms
AC Voltage
Range | Resolution | Input Impedance | Accuracy |
500mV | 0.1mV | 1MΩ |
Not specified |
5V | 0.001V | 50-60Hz ± (1.2% of rdg + 5 dgts) 60-500Hz ± (2.0% of rdg + 5 dgts) |
|
50V | 0.01V | ||
500V | 0.1V | ||
600V | 1V |
Overload Protection: 600V DC or AC rms
DC Current
Range | Resolution | Accuracy |
200A | 0.1A | ± (2.0% of rdg + 5 dgts) |
Maximum input current: 200A
AC Current
Range | Resolution | Accuracy (50 to 60Hz) |
200A | 0.1A | ± (2.0% of rdg + 5 dgts) |
Maximum input current: 200A
Frequency
Frequency measurement using AC current range
Range | Resolution | Accuracy |
30Hz to 400Hz |
0.1Hz | ± (0.1% of rdg + 5 dgts) |
Input sensitivity > 10A AC rms
Maximum input current: 200A AC rms
Resistance
Range | Resolution | Open Circuit Voltage | Accuracy |
500Ω | 0.1Ω | -3.2V DC | ± (1.0% of rdg + 5 dgts) |
5kΩ | 0.001kΩ | 1.1V DC Approx | |
50kΩ | 0.01kΩ | ||
500kΩ | 0.1kΩ | ||
5MΩ | 0.001MΩ | ± (1.5% of rdg + 5 dgts) | |
50MΩ | 0.1MΩ | ± (3.0% of rdg + 5 dgts) |
Overload Protection: 600V DC or AC rms
Continuity
Range | Resolution | Response Time | Accuracy |
500Ω | 0.1Ω | 100ms | <30Ω |
Overload protection: 600V DC or AC rms
Additional Technical Specifications can be found in the attached datasheet.