TENMARS ELECTRONICS
TENMARS ELECTRONICS TM-508A Milliohm Meter 1 mΩ–20 kΩ six steps
Measures resistance from 1 mΩ to 20 kΩ in six switchable steps using four-wire clips with a 2000-count LCD display
- TypeTest Equipment
- Color/FinishRed
- Item Count1 pack
- Selling UnitBox
- Parts3 Years
- Labor1 Year
- Wide 1 mΩ–20 kΩ range in six switchable steps
- Four-wire Kelvin clips eliminate lead resistance for accurate low-impedance readings
- External zero adjustment removes offset before each measurement
- 3½-digit 2000-count LCD with data-hold locks the displayed value
- Fused 2 A/250 V input protects the meter during fault conditions
Purpose & User
The TENMARS TM-508A is a four-wire milliohm meter built for electricians and technicians who need to verify very low resistances. It measures from 1 milliohm up to 20 kilohm across six switchable steps. The 3-1/2 digit LCD shows readings up to 2000 counts. External zero adjustment lets the operator compensate for lead resistance before each test.
Thermals, Noise & Power
The instrument runs on an internal battery that is not supplied in the box. A 2 Amp 250 Volt fuse with a 1500 Amp interrupt rating protects the input circuitry. No cooling fan is present, so operation is silent. Power draw is limited to the measurement circuit and the LCD display.
Accessories & Software Impact
One pair of insulated clips is included for four-wire connection. A D-H switch locks the displayed reading for later review. Low battery indication warns when supply voltage drops. The red case measures 160mm by 100mm by 52mm and weighs roughly 700g. The supplier covers parts for three years and labour for one year.
Highlights
- Wide 1 mΩ–20 kΩ range in six switchable steps
- Four-wire Kelvin clips eliminate lead resistance for accurate low-impedance readings
- External zero adjustment removes offset before each measurement
- 3½-digit 2000-count LCD with data-hold locks the displayed value
- Fused 2 A/250 V input protects the meter during fault conditions
Specifications
| Brand | TENMARS |
|---|---|
| Model | TM-508A |
| Type | Test Equipment |
| Color/Finish | Red |
| Item Count | 1 pack |
| Selling Unit | Box |
| Parts | 3 Years |
| Labor | 1 Year |
Questions about this item
How do I connect the four-wire clips and set the zero adjustment on the TM-508A?
Attach one pair of insulated clips to the test points, then turn the external zero-adjustment control until the 3-1/2 digit LCD reads 000 before measuring.
Which user-replaceable parts will need attention after extended use on the TM-508A?
The 2 A / 250 V (5 mm × 20 mm) fast-blow fuse rated for 1500 A interrupt and the battery (not included) are the only routine replacements.
At what point does the TM-508A stop displaying higher resistance during sustained testing?
The 2000-count LCD caps the reading at 2000 on the selected range, so values above that show as over-range until you step to a higher range.
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