DUOYI DY4100 Digital Earth Ground Resistance Tester Multimeter Resistance Measurer

The meter and accessories are well made but the bag won't last too long if constantly used.Trying to understand the instructions is difficult: firstly, note the page ordering (in small numerals at the bottom of each folded section). The poor English is confusing but there are some diagrams that might help. Basically there are two procedures, which I will outline below:1. Measuring the Earth Voltage: (do this test first)Why do this? I think it's to check there are no interfering voltages in the ground you are testing.a. Setup the meter and leads as shown in the diagram on page 5.b. Then plug the E lead into the V socket on the meter.The setup now looks like the diagram on page 6.c. Set the switch to EARTH VOLTAGEd. Read the LCD display and make sure it's less than 10 volts.e. Set the switch to OFF.f. Plug the E lead back into the E socket on the meter.2. Measure the Earth Resistance: (do this test second)Why do this? To measure the resistance of the earth rod you've just installed.a. Setup the meter and leads as shown in the diagram on page 5.b. Set the meter switch to 2000 ohms.c. Prest the TEST button and take an EARTH RESISTANCE reading.d. If no reading then set the meter switch to 200 ohms.e. Press the TEST button and take an EARTH RESISTANCE reading.f. If no reading then set the meter switch to 20 ohms.g. Press the TEST button and take an EARTH RESISTANCE reading.The rest of the instructions (starting on page 6) and the diagram on page 7 show an alterative way of measuring the EARTH RESISTANCE if you can't connect the E lead directly to the Earth rod under test.I tested the meter using the normal procedure outlined above. After driving in an 8 foot earth rod into fairly hard ground I measured an EARTH VOLTAGE of 0.2V and an EARTH RESISANCE of between 125 and 178 ohms (depending on the soil conditions); anything under 200 ohms is acceptable.