I recently purchased a pair of WEM3080T to undertake the combined Grid and Solar Inverter measurement on a 3 phase system but am struggling to see how to provide the feed in to the meter from the load side of the Henley Block as all the cabling is heavy duty (12mm) including on the load side, whereas the connection size to the meter UA UB UC UN is much lower rating. How would you ‘step down’ the cable size given the differential…?
This is the wiring diagram about using two WEM3080T to monitor 3phase grid and 3phase inverter output
https://www.iammeter.com/docs/wiring-diagram#3-three-phase-solar-pv-system-and-3-phase-grid-system
For your question ,I try to ask chatgpt and it replies me as below
If you need to connect thinner wires, you can still use Henley Blocks, but you should keep the following points in mind:
1. Choose the Right Terminal Size
Henley Blocks typically come with various terminal sizes. Make sure you choose a terminal that is suitable for the thickness of your wire. For thinner wires, select a Henley Block with smaller terminals to ensure a secure connection. The wire size compatibility will usually be indicated in the product specifications.
2. Use Adapters or Connectors
If you find that the Henley Block terminal is not a perfect fit for your thin wire (for example, if the wire is too thin), you can use an adapter or connector. First, connect the wire to the adapter, and then connect the adapter to the Henley Block terminal. This will ensure that the wire has a good connection with the terminal.
3. Ensure Good Contact and Tightening
Even with thinner wires, make sure the wire is securely compressed and makes proper contact when connecting to the Henley Block. Loose connections can cause unstable current flow or overheating issues. Use the appropriate screwdriver to tighten the connections and prevent the wire from loosening.
4. Check the Current Load
Thin wires typically have a lower current capacity, so be mindful not to overload the wire. Ensure the wire is capable of handling the current you expect to pass through it. If the current is high, you may need to use thicker wires.
5. Use Proper Wiring Tools
Thinner wires tend to be more flexible and can be easily damaged. Use the right tools, such as a professional crimping tool, to ensure a secure connection without damaging the wire.
6. Verify the Safety of the Connection
After making the connection, check each terminal to ensure it is tight and secure. Look for any loose connections or signs of wear. It’s also a good idea to test the connection with a voltage tester to ensure everything is functioning properly and safely.
Thanks for this but the nub of the issue is 4: check the current load
Thin wires typically have a lower current capacity, so be mindful not to overload the wire. Ensure the wire is capable of handling the current you expect to pass through it. If the current is high, you may need to use thicker wires.
The cable size/load capacity on the meter looks to be minimal whereas the load on the supply is large (commensurate with a 3 phase system)?
Hi,
Apologies for not explaining this more clearly earlier.
The Ua, Ub, Uc, and Un serve two functions:
Sensing the 3-phase voltage independently (you can consider this as a high-impedance input, so there’s no need to worry about the cable width).
Powering the meter (this requires considering the cable width based on the meter’s power consumption).
For the second function, the power consumption of the meter is very low—around 2W. Taking a 200V voltage input as a reference, it only requires a current of 2W/200V = 10mA. This is a very low current, so there’s also no need to be concerned about the cable width.
Let me know if you have any further questions or need additional clarification.