CTid Overview


Correctly identifying and configuring specific CT types is a crucial part of any eGauge installation. Typically, this is done by examining each CT, making a note of the manufacturer, inner diameter, and amperage rating, and selecting the correct option for that CT on the Installation page. With CTid, the eGauge gains the ability to scan connected CTs and obtain this information automatically. CTid functionality is only available in EG4xxx (eGauge Core and Pro) hardware. EG30xx and older meters do not support CTid. Special CTid-compatible CTs are also required.


CTid CTs can be queried by the eGauge to determine manufacturer, physical size, and amperage rating. CTid cannot determine CT/voltage reference pairing (phasing). This information is still critical for a correct installation, regardless of whether CTid CTs are used.


The eGauge can be used with a mixture of CTid and non-CTid CTs. CTs without CTid will not be recognized when scanning for connected CTs, and must be configured manually.


Using CTid


1. Navigate to the Installation page (under Settings -> Installation). Click the blue CTid button. This will load the CTid scanning utility. Valid credentials are required to load this utility.


Figure 1: Installation Page with CTid button highlighted


2. Select the CT inputs to be scanned. In the example below, CT inputs 1 through 6 were selected, but CTid CTs were only connected to ports 1-3. Note that a red X will appear when a non-CTid CT is connected and when no CT is connected. The scan takes several seconds per CT, so it is recommended to only select inputs in use. Click the “Scan Checked CTs” button to start the scan.


Figure 2: List of detected CTs (scan on ports 1-6, with CTs on ports 1-3)


3. Once the scan is complete, click “Back to Settings”. This will load the Installation page. Detected CTs will be listed in blue. CTid will overwrite existing CT selections if a CTid-compatible CT is detected on an input. Inputs with no CTs or CTs which do not support CTid will remain unchanged. Note that CTid only identifies connected CTs - registers, CT/phase pairing, and any other configuration details must still be entered manually or the eGauge will not record correctly.


Figure 3: CTs detected by CTid will be highlighted in blue


Additional Features


CTid Details - displays additional information about the detected CTs. Click the to the left of a detected CT to display this information. The information listed may vary from CT to CT, depending on the manufacturer and type of CT. 


Figure 4: CT details page for a Magnelab Rope CT.



CTid Blink - Causes the LED built into the CTid CT to blink. This can be used to determine which CT is connected to a given input Only one CT can be set to blink at a time. This is particularly useful if CT leads pass through conduit or another condition prevents CT wires from being traced. This is also a useful tool to help determine the correct CT/phase pairings.

Figure 5: CTid Blink button (highlighted)



Figure 6: The location of the LED may differ based on the CT type.