Description
The TENTECH MD542 is a smart, microprocessor controlled, 500 V insulation tester for up to 100 GΩ @ 500 V resistance measuring with 100 V, 250 V and 500 V test voltage. It is a portable, handheld, battery-powered equipment.
Due to its measurement principle (actual voltage and current readings) it is a "true megohmmeter" and so the accuracy of resistance measurement is not affected by any test voltage error
Operation is very simple and user-friendly: just connect the leads, switch-on the equipment, select the test voltage and press the start button. Then the equipment automatically selects the most suitable scale and shows the measured value in the digital display.
In order to guarantee the operator safety there are no accessible metallic parts. Output terminals are placed in the furthest and most protected area of the equipment. A light indicator shows high-voltage presence and is switched-off when the capacities (both internal and external) are discharged up to reaching a safe value.
Furthermore, it offers useful additional features: 200 mA continuity range, low resistance measurement, AC/DC voltage measurement up to 400 V, selectable timer, hold memory, and selectable resistance limits for pass-fail testing, with acoustic indication.
Surface leakage paths may affect the measurement of high value insulation resistance. The use of the GUARD terminal permits to remove the effect of this current, substantially improving the test result.
Specifications
Nominal test voltages
100 V - 250 V - 500 V
Negative, DC voltage
Resistance measurement range
From 10 kΩ up to 100 GΩ
Short circuit current
1.5 ± 0.3 mA
Test voltage accuracy
-0 / +15 % for resistances between 5 MΩ and open circuit.
Basic accuracy
R ≤ 50 GΩ: ± 5 % of reading ± 2 digits.
R > 50 GΩ: ± 10 % of reading ± 2 digits.
Low resistance measurement and continuity tester
Range: 0.05 Ω to 150 Ω
Accuracy: ± 5 % of reading ± 2 digits
Test current: up to 200 mA
Continuity indicator: Activates at R < 5 Ω ± 0.5 Ω
Built-in timer
5 - 10 - 15 - 30 seconds
1 - 2 - 3 - 5 - 10 - 15 minutes
Pass / fail test
0.2 - 0.3 - 0.4 - 0.5 - 0.6 - 0.7 - 0.8 - 0.9 MΩ
1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 20 - 30 - 40 - 50 - 60 - 70 - 80 - 90 - 100 - 200 - 300 - 400 - 500 - 600 - 700 - 800 - 900 MΩ
1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 GΩ
Voltmeter True RMS
Range: 0 - 400 VAC/DC
Accuracy: ± 3 % of reading ± 2 digits
Additional features
• Automatic polarization index
• Guard terminal
• Hold function
Overvoltage protection
600 V
Safety class
In accordance with IEC 61010-1.
E.M.C.
In accordance with IEC 61326-1.
Electrostatic immunity
In accordance with IEC 61000-4-2.
Electromagnetic irradiation immunity
In accordance with IEC 61000-4-3.
Power supply
Built-in, NiMH battery
Autonomy: 1000 tests of 5 seconds with an interval of 25 seconds according IEC 61557-2. During the measurement is used a test resistance which the value is UN x (1000 Ω / V).
Battery charger
Built-in, with external power supply of 12 V - 2 A.
Operation temperature
14 °F to 122 °F (-10 °C to 50 °C).
Storage temperature
-13 °F to 158 °F (-25 °C to 70 °C).
Humidity
95 % RH (without condensation).
Equipment weight
Approx. 1.1 lb (0.5 kg).
Dimensions
4.01" x 7.68" x 1.81" (102 x 195 x 46 mm).
