Suitable for secondary development, online monitoring of loop grounding resistance and metal loop connection resistance, grounding condition monitoring. 1. Model No.: ETCR2800T 2. Measurement Range: 0.01Ω~100Ω; 3. RS485 communication protocol(support MODBUS) 4. Output Range : 0.00Ω~100Ω 5. Accuracy: ±2%rdg±3dgt (20℃±5℃,below 70%RH). 6. Power Supply: 6VDC~9VDC,50mA Max.(External power supply)