CT Clamp
A CT clamp is a device for measuring electric current and giving the direction of the flow for solar inverter, which is in fact a current sensor.
CT clamp Specification
| Model | Parameters |
| Current Ratio | 1000:1 |
| Max Current | 100A |
| Min Current | 100mA |
| Rated Primary Current | 5-400Aac |
| Maximum Primary Voltage | 5000Vac(insulated conductor) |
| Rated Secondary Voltage | 0.333Vac |
| Operating Temperature | -15℃ to +60℃ |
| Operating Frequency | 50-400Hz |
| Operating Humidity | <85% |
| The Length Of The lead | 10m |
| Accuracy | Class 1.0 maximum |
| Case Material | PC/UL94-V0 |
| Environmental Protection | RoHS compliance |
| Phase Angle | Less than 2 degrees at 50% of rated current |
| Certification | Compliance with CE requirements |
Meter overview(optional)
The meter appearance and dimensions are shown below figure as a reference.
| No. | Function Pin | Remarks |
| 1 | Live Line Input | Input of internal current sensor |
| 2 | Live Line Output | output of internal current sensor |
| 3 | Neutral | |
| 4 | Neutral | |
| 5 | Pulse 1 out+ | |
| 6 | Pulse out- | |
| 7 | Pulse 2 out+ | |
| 8 | RS485 GND | |
| 9 | RS485 B | |
| 10 | RS485 A |
Pulse Output Connection
Pulse output must be fed as shown in the wiring diagram right-side.
Scrupulously respect polarities and connection mode.
Opto-coupler with potential-free SPST-NO Contact.
Contact range:5-27Vdc Max
Current input: 27mAdc
Meter Specification
| Model | SDM120 Modbus Pin |
| Nominal Voltage(Un) | 120V.a.c or 230 V.a.c |
| Operational Voltage | 80%-120% of Un |
| Basic Current (lb) | 5A |
| Maximum Rated Current (Imax) | 45A |
| Operational Current Range | 0.4 lb-Imax |
| Over Current Withstand | 30 Imax for 0.01s |
| Pulse Output | 1000imp/kWh |
| International Standard | IEC62053-21/EN50470-1/3 |
| Accuracy Class | Class1/Class B |
| Installation Category | CAT ∥ |
| Mechanical Environment | M1 |
| Electromagnetic Environment | E2 |
| Degree of Pollution | 2 |
| Ingress Protection Degree | IP51(indoor) |
| Voltage Current Accuracy | 0-5% |
| Frequency Accuracy | 0-2 of mid-frequency |
| Power Factor Accuracy | 1% of utility(0.01) |
| Active&Apprarent Power | ±1% of range maximum |
| Reactive Power Accuracy | ±1% of range maximum |
| Active Energy | Class1 |
| Ingress Protection Degree | Class2 |
CT clamp and meter connecting and setting are easy. If you want to know more, please click "What is a CT clamp?" and if you want to know more professionally, please download the PDF.
