Status page showing 1100hz, 0 volts on all CT's and VT - diagnosed

Hi all, I have just installed an Iotawatt and it doesn’t seem to be working properly, I’m assuming I’m doing something wrong. My building has 208v 3 phase power, but the panel I’m monitoring is only single phase, fed by 2 hots, a neutral, and a ground. I have a TDC DA-10-09-E6 connected for my 9v AC reference ground, and a 5v USB DC adapter. For my CT’s, I’m using 2x AcuCT-H063-100, 1 connected to each hot leg. Here are pictures of my panel:

Here’s a screenshot of my status page, which obviously shows I have done something wrong!

The immediate issue is that the voltage reference isn’t working. You might check if the transformer is putting out any voltage.

Once you get a voltage reference, you will need to treat your service as three-phase using derived reference. You only have two of the three phases, but that’s ok. You cannot treat it as single or split phase.

Thanks, I just checked and I’m not getting ANY voltage out of that adapter. What’s the warranty on that? I literally just pulled it out of the box yesterday, but I purchased everything a year ago January.

I stand behind things for a year. I’ve never had one of those DOA. If you send it back to me, I’ll send you a replacement part, but I don’t have any of those TDC anymore.

Have you tested it in a different receptacle?

Hello, I have tested on multiple outlets. How do I go about returning this?


Hello, i received the replacement transformer and am now seeing 60hz, great! Next, I went through the documentation about setting up derived reference. It states to connect CT’s to each of the 3 phases, but in this panel I only have 2 legs. Any hints on how to proceed on that?

Just use two. The one with the VT is phase A, the other will be either phase B or C.

Thanks, it looks like I may have things configured properly now?

Not really. Which of the breakers in the picture feeds the receptacle where the AC transformer is connected?

The VT is connected to Input 1

Read the question again.

This breaker here:

I just changed the config around so the VT is setup on the same phase as input 1 and unchecked “allow negative value”:

Here’s the status page now:

So input 1 is the CT on the black wire?

Click reverse in the input0 setup.

Then post the status display.

Correct, Input 1 is connected to the CT on the black wire. Here’s a screenshot:

Change input_2 to phase C

Done, here are some screenshots:

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Now that I have a few days of tracking, does this graph look correct? It seems like they shouldn’t look so different from each other?

You don’t have any 240V loads, so the two are completely independent. Without CTs on the loads and/or some knowledge of what they are powering, I have no idea. They are certainly plausible.

Input_1 seems to have a constant load of about 140Watts and a transient load of about 180Watts.
Input_2 appears to have a constant load of about 90Watts, and transient loads of about 130 Watts and 50 Watts.

Does that sound like your regular loads?