Low resistance measurement is the standard test for determining the condition of joined junctions like circuit breaker and relay contacts and terminals. Ideally, joined metals should have a very low resistance on their junction. However, when the joint weakens, forms carbon deposits, grease, dirt and other contaminants, the resistance increases. This can be a problem because the junction may not efficiently carry the current and dissipate the power losses as heat. This may lead to further deterioration and eventual failure.
Ordinary multimeters have a limited resistance range which is not suitable for low resistance measurement. In order to accurately measure extremely low resistances, a MicroOhmmeter is used. This device has a special input circuitry that isolates the lead and other stray resistances to ensure accurate results. Nowadays, MicroOhmmeters are microprocessor based for enhanced diagnostics, protection features and automatic range selection. These devices are called Digital Low Resistance Ohmmeters or DLROs. These meters can definitely save you a lot of time in low resistance measurement.
If you are planning to get a DLRO, you might be interested in Megger’s DLRO 10 or DLRO 10X MicroOhmmeter. These devices are fully automatic which set the appropriate current and resistance range. They also have multiple security features to ensure safe operation. Read on to compare the features of each tester.
Megger DLRO 10 MicroOhmmeter
The DLRO 10 offers basic low resistance measurement ideal for testing bus bars, switch gears, motors, transformers and other electrical equipment. It offers three testing modes depending on the test you need to carry out.
Product Features
- Auto Range and Auto Current setting
- Measures resistance from 0.1 μΩ to 2000 Ω
- Large 4 1/2 digit LED screen
- Measures resistance within 3 seconds
- ±10% accuracy
- Normal, Auto, Continuous and Inductive modes
- Single cycle reversing Direct Current radiometric measurement
- Powered by a rechargeable 7Ah NiMH battery
- Can conduct 1000 10-Ampere tests before recharging
- >200 kΩ input impedance
- Battery condition indicator
- Checks for noise during measurement
- 2.6 kg
- IEC61326-1 and IEC61010-1 600 V CAT III compliant
Megger DLRO 10X MicroOhmmeter
This is an improved version of the DLRO 10 model. It has a menu system that gives you more control of the measuring process. It has internal memory storage so you can store results for later retrieval. You can also connect this device to a computer to transfer the results and for storage. The DLRO 10X features a unidirectional mode that applies current to one direction. This test mode helps speed up the measurement of resistance.
Product Features
- Auto Range and Auto Current setting
- Large backlit LCD screen
- Measures resistance within 3 seconds
- ±10% accuracy
- Normal, Auto, Continuous, Unidirectional and Inductive modes
- Single cycle reversing Direct Current radiometric measurement
- Powered by a rechargeable 7Ah NiMH battery
- Can conduct 1000 10-Ampere tests before recharging
- >200 kΩ input impedance
- Checks for noise during measurement
- Battery condition indicator
- 2.6 kg
- IEC61326-1 and IEC61010-1 600 V CAT III compliant
- RS232 connectivity for real-time data transfer or store test results on a computer
- Internal storage that lets you store up to 700 test results
- Memo field which allows you to put up to 200 characters on each test
- You can set an upper and lower limit for a go or no-go testing
- Displays both forward and reverse test results
- Two-axis paddles for manually selecting the max test current
For basic low resistance measurement the DLRO 10 is sufficient for most applications. However, if you need an advanced tester with more testing options, PC connectivity and internal storage, the DLRO 10X is the best choice. Both testers offer reliable and accurate operation. They are also made from durable materials which ensures that they will last for a long time. You can be confident that you’ll be getting the best value for your money.
Protec Equipment Resources is a test equipment provider you can trust. You have several equipment acquisition options to choose from to suit your needs. Please contact our specialists today for assistance and for a quote.