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Hi Greenbeast, do you have the complete Harvells Tri-Load board or just the display/meter.

I think they are designed to work with Harvells'
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own integrated CTs...

Here's the spec if you don't already have it for the meter You should be able to cycle through the display and see phase voltages (to neutral) and phase currents, overall pf.

Have you got 3 times CTs installed, one for each phase?

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Discussion Starter · #6 ·
This was early on in the install.
No don't have the havells board, but do have the matching CT clamps. I received a set of 3 which initially confused me but I see they are 3x60A, 3x125A and 3x200A,so presumably for different applications, I went for the 125A model.
I do have CanZE but didn't think to check it at the time

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This was early on in the install.
No don't have the havells board, but do have the matching CT clamps. I received a set of 3 which initially confused me but I see they are 3x60A, 3x125A and 3x200A,so presumably for different applications, I went for the 125A model.
I do have CanZE but didn't think to check it at the time

View attachment 150215
As well as cycling through the display, measuring phase voltages with a DMM and checking on CanZE
you might want to think about swopping out the 125A CT set for the 60A CT set in case you have a faulty CT.

But defintely measure the phase voltages first and check on CanZE that the car is charging OK before changing your metering/monitoring setup.

I'm assuming this is all NEW kit purchased through a ligit distributor?
 

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Discussion Starter · #8 ·
As well as cycling through the display, measuring phase voltages with a DMM and checking on CanZE
you might want to think about swopping out the 125A CT set for the 60A CT set in case you have a faulty CT.

But defintely measure the phase voltages first and check on CanZE that the car is charging OK before changing your metering/monitoring setup.
Thank you

I'm assuming this is all NEW kit purchased through a ligit distributor?
🤣🤣🤣
But seriously, the meter and clamps were all unused and still in original packaging.
 

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I noticed your wiring uses 3 brown wires for the phase voltages. Ideally you would use consistent colours for L1, L2, L3 for the main supply and the wiring to the monitor, ie brown, grey and black. Are you sure you have not mixed up your wiring?????
 

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Discussion Starter · #13 ·
I noticed your wiring uses 3 brown wires for the phase voltages. Ideally you would use consistent colours for L1, L2, L3 for the main supply and the wiring to the monitor, ie brown, grey and black. Are you sure you have not mixed up your wiring?????
I have double checked that, but I can triple check it. Also I could put some effort into finding appropriately sized and coloured replacement. I think I was trying to finish up
 

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Have a read of the following:- (from a very good quality 3 phase power meter).

Worst case is that there is a lot of DC (waveform distortion from the Zoe)



There are a variety of possible measurement problems. The following procedure should help narrow down the problem. This assumes you can communicate with the meter and read registers. You can combine these diagnostic steps with the status LED diagnostics. Voltage Start by checking the reported voltage (VoltA, VoltB, VoltC) for active (connected) phases. Make sure the voltages match the expected line-to-neutral voltages (or line-to-ground for delta circuits). You should check the actual voltages present at the meter with a multimeter if possible. If one or more voltages are zero, then you either have a wiring problem or something is wrong with the meter. Verify the actual voltages with a multimeter. In rare cases, with delta circuits, one phase may be grounded and will read zero volts. If one or more voltages are too low (by more than 5%), then make sure you have the correct model. For example, a VPA.8000.Y208 expects line-to-neutral voltages of 120 Vac and can measure up to about 150 Vac. If you apply 208 Vac line-to-neutral, the meter will read a voltage in the 150 Vac to 180 Vac range. If any voltages read high, then check your wiring. If the wiring is correct, contact support. If the voltages are close to the measured (or expected) values, continue with the next step. Power Next, check the measured power for each active phase (PowerA, PowerB, PowerC). If possible, estimate or measure the actual power. Also, make sure the load you are measuring is currently on. If one or more active phases are reporting zero power, then the problem is probably one of the following: o There is no active power (the load is off) or the power is too low to measure (generally less than 1/1000th of full-scale). o CT wires are not securely connected. o The CT or its wires are damaged. o There is strong electrical interference, as might occur if the meter is in very close proximity to a variable speed drive (also called variable frequency drive or inverter). o The meter is not working correctly: try swapping it with a replacement meter. If one or more active phases are reporting negative power: o The current transformer has been installed backward on the wire being measured. CTs are marked with either an arrow or a label saying “This side toward source”. If the arrow or label are not oriented toward the source of power (generally the panel or breaker), then the measured current will be inverted and the power negative. This can be fixed either by flipping the CT or by swapping the white and black wires where they enter the meter. o The current transformer white and black wires have been swapped where they enter the meter (at the black screw terminal block). o The line voltage phases (green screw terminals) are not matched up with the current phases (black screw terminals). For example, the phase A CT is around the phase B wire. o This may be normal if you are measuring in an environment were power may be consumed or generated, such as a house with PV panels. If one or more phases are reporting low or high power: o Make sure the CtAmps configuration is set correctly for your current transformers. o The current transformers may have a rated current too high or too low for your application. CTs should be used between 10% and 100% of their rated current for best results. They generally work with reduced accuracy as low as 0.5% to 0.1% of rated current. o The CTs may not be installed properly. Check for: CTs touching each other or pre- existing CTs; CT opening too large for the conductor being measured. o The voltage phases (green screw terminal block) are not matched up with the current phases (black screw terminal block). The easiest way to determine this is to skip ahead to the next troubleshooting section: Power Factor and Reactive Power. o Interference from a variable frequency or variable speed drive: VFD, VSD, inverter, or the like. Generally, these drives should not interfere with the meter, but if they are in very close proximity, or if the CT leads are long, interference can occur. Try moving the meter at least three feet (one meter) away from any VFDs. Use short CT leads if possible. NEVER install the meter downstream of a VFD: the varying line frequency and extreme noise will cause problems! o Our current transformers can only measure AC currents. Strong DC currents will saturate the magnetic core of the CT, preventing an accurate measurement of the AC current. The overwhelming majority of AC powered electric devices do not draw significant DC current, so this is a rare occurrence
 

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What model of Zoe? Attached curve is voltage current for a Q (only showing voltage and current for one phase) showing current distortion
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Discussion Starter · #16 ·
Have a read of the following:- (from a very good quality 3 phase power meter).

Worst case is that there is a lot of DC (waveform distortion from the Zoe)
Thanks, none of the issues discussed in that are present here. No VFDs present, short line voltage sense wires, no line wires are the wrong direction, the CT holes are an appropriate size for the cross-section of wire being used. There are appropriate voltages on all 3 phases under load. I checked the meter's current register (picture included), also checked CanZE (screenshot included)

Very odd.
I do plan to run another supply through one of the CT holes so I can meter a single phase consumer unit (feeding my flat), currently that runs through CT 2 (and is not even live yet) but I might switch it to CT 3 to test it when I make it live
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It's got all the hallmarks of being a CT problem. Looks very much as if one of the CTs isn't working and the two that are have either the wrong burden fitted or the meter hasn't been set up for them. IIRC, the burden on these is as it should be, integrated into the CT (to reduce the electric shock risk). Not unusual to find CTs with no integrated burden, though. They can give a hell of a nip with just an amp or two flowing through the cable, due to the high turns ratio. Found this out the hard way fitting some cheap CTs (no prizes for guessing where they were made). I (stupidly) assumed the CT leads would only have a tiny potential, in reality they were a few hundred volts, as the damned stupid design of the thing had the burdens fitted inside the meter, meaning the CTs were unloaded if not connected.
 
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