Since the release of the V5 firmware we have seen a lot of comments on the forum about the "Grid CT Lost" warning message.
There are also some devices that will boost but won't track surplus.
This article provides some information on what causes this warning and how to fix it.
In this article:
- What's changed in V5?
- Why do I get the Grid CT Lost warning after upgrading to V5?
- What to check if you get the Grid CT Lost warning
What's changed in V5?
In previous versions of our firmware the Grid CT Lost feature only worked on zappi and only on the device that had the CT's hardwired to it. Any other devices in the network could still take power even if there was a problem with the Grid CT which meant that the Grid Limit might not always work.
With V5 we've improved this feature so that all myenergi connected devices will turn off their output if the Grid CT is lost.
This is important, not only to protect the Grid fuse but also to meet new regulations that are being introduced to support the installation of more "Energy Smart Appliances" such as EV chargers, battery storage, heat pumps etc.
Why do I get the Grid CT Lost warning after upgrading to V5?
In nearly every case we have looked at the problem is down to the configuration of the myenergi system - it boils down to two main issues
- CT's incorrectly configured or missing
- There's no "master" device in the network
What to check if you get the Grid CT Lost warning
Is there a "master" device in the network?
- On any zappi, eddi or libbi in your setup, go to the Linked Devices Info page.
- In the list of devices there should be one, and only one, with an "M" next to it.
If not, then choose your master device (this would normally be the one with the Grid CT's wired to it and/or it will be paired with any harvis you have)
- Go to the Advanced - Linked Devices menu
- Make sure there is a tick next to the "Set Master" menu item
Are the Grid CT's set correctly?
myenergi devices are designed to work with a Grid CT (or a set of three Grid CT's in a three phase system). These are essential if you want to make the most of any local PV or wind generation but also allow you to track your energy usage in the myenergi app and online account. Some installations do not have a Grid CT - that's OK, but read on to make sure the CT's are set set correctly.
Grid CT's are physically connected either wired directly or to a harvi
- How many CT's (or sets of CT's) have the CT Type set to "Grid"?
- If more than one, identify which ones are being used to measure the Grid power flows
- Set the other CT's "CT Type" to "None" (or to the correct CT type if they are being used to measure a different power flow)
There are no Grid CT's installed
- In this case there must be no CT's in the system that are set to the CT Type "Grid"
- Make sure that all CT's have their type set to "None".
The CT Type is set on the following menus:
- For hardwired / directly connected CTs: Advanced - CT Config
- For CT's on a harvi, the menu is on the "master" device: Advanced - Linked Devices - Devices - harvi
You can quickly check your Grid CT and Master settings by looking on the Linked Devices Info menu on your Master device
Note: If your Grid CT is connected to a harvi, the Grid CT symbol ~ will only be visible on your Master Device
Should I turn off CT Detect?
No! That's the simple answer. As long as you are using the latest firmware (see: Current firmware versions / updating your firmware) and follow the guidelines on this page then there should be no need to turn off the CT Detect feature.
With previous firmware, if there were no Grid CT's, one workaround was to set one CT type to "Grid" and then to turn off the CT Detect. With V5 firmware this workaround is no longer valid.
If there are no Grid CT's fitted then all CT's should have the CT Type set to "None"