Can I use any CTs with my eGauge?
If you bought your CTs from us, you can be assured they will work with your eGauge. While we support a broad range of CTs that may be available from other sources, not all CTs are compatible with every meter. For a complete list of supported CT models and their current ratings, please refer to the eGauge CT Compatibility List.
Note: Supported CTs purchased from sources other than eGauge will not include 2-pin terminal connectors necessary for installation. They are available in our Web Store.
Caution!
To reduce risk of electric shock, open or disconnect circuits from the power distribution system (or service) of the building before installing or serving CTs.
Step 1: Open the CT by gently releasing the latch and then opening the CT wide enough to position over the conductor to be monitored. Do not touch the surfaces inside where the CT opens. Any oils or debris in that area worsens accuracy.
Step 2: Slide the CT over the conductor of the circuit to be measured. Make sure the sticker on the CT points in the direction of the primary current flow (the current flow that should yield a positive power reading).
Step 3: Close the CT by engaging the latch. See the sections below for specific information depending on your CT type.
Step 4: Verify that the CT is fully closed by squeezing together the top and bottom parts of the CT for split-core CTs. When installing rope CTs make sure the latch is fully engaged.
Step 5: Optional: secure the CT to the conductor with a cable tie.
Step 6: Route the twisted pair wires of the CT to the meter such that they do not directly contact live terminals or bus bars.
Step 7: Plug the 2-pin terminal at the end of the twisted pair wires into an unused port on the meter lining up the black and white leads with port markings as shown below:
Step 8: Using a handheld volt meter, verify CT phasing by taking a voltage reading between the monitored conductor and the eGauge AC Voltage ports. Check L1, L2 and L3 and make a note of the CT port used and the voltage port where you see a 0 VAC reading between points as shown in the graphic below.
Step 9: Record the eGauge sensor port used, CT model and Amp rating as well as the monitored load and phase verified in the previous step for reference. This information will be needed later for proper meter configuration. Use the Installation information pages in the back of the manual, or create your own spreadsheet to record this information.
Example:
Sensor port# | CT Model | Phase | Measured Item |
| 1 | JS10FL-50 | L1 | Common area lights |
| 2 | JS10FL-100 | L2 | Kitchen outlets |
| 3 | LS16FL-100 | L1 | Basement outlets |
Split Core CTs should close fully and easily around the conductor to be monitored without forcing. If the CT is too tight around the conductor it can affect readings. CTs should be able to close fully, a CT that is partially opened will not read correctly.
Split core CT model and Amp rating information is found on the label affixed to the CT body. Different brands of CT may look slightly different than the example in the photo, but the information will generally be found in the same place.
| CT Brand & label | Orientation for Positive Readings |
|---|---|
| AccuEnergy AcuCT-3135R-xxxx:333 | Arrow same direction as power flow |
| eGauge Systems ECSxx-xxx (CTid) | Arrow same direction as power flow |
| J&D JSxxFL-xxx | Arrow against direction of power flow |
| CCS ACT-xxxx-xxx-C06 | Sticker against direction of power flow |
ERA-xxx-yyyy CTid enabled Rope CT - Open by gripping and twisting the bayonet connector and pulling the end of the rope CT out. Exact model with CTid logo is found on the tag attached to the lead.
RCT-xx-yyyy AccuEnergy Rope CT- Open by gently squeezing the latching mechanism on the sides and pulling the CT open. Exact and current rating is found on the tag attached to the lead.
Rope CTs should be positioned with the conductor as centered as possible. Twisting or distorting the flexible coil can contribute to inaccuracy.
| CT Brand & label | Orientation for Positive Readings |
|---|---|
| eGauge Systems ERA-xxx-yyyy | Arrow against direction of power flow |
| AccuEnergy RCT-xx-yyyy | Arrow against direction of power flow |
Sensor hub (ESH044) - The eGauge Sensor hub is needed to connect any of the CTid environmental sensors to the eGauge.
4-20mA Sensor (EC420) - Reads 4-20mA output from a variety of third party sensors.
Temp Probe (ETN100) - Temperature probe.
Ambient Temp Sensor (ETLW) - Ambient temperature sensor.
Pulse Sensor (EPS) - Read pulse output into the eGauge.
0-2V Analog Input Sensor (ELV2) - Read 0-2V DC output into the eGauge.
High Voltage Sensor (EV1000) - Read up to 1000VDC or 707VAC.
DC CTs with CTid - Monitor DC current.
Extending AC CT Leads
- 18 ga. twisted pair wiring, or Cat 5 cable (1 twisted pair per CT) is recommended.
- Splices should be soldered or completed using appropriate connectors such as the eGauge CT Extension Pack. Wire nuts should not be used.
- Extensions recommended not to exceed a maximum of 100 feet.
- Avoid running alongside any high voltage wiring to reduce the potential for interference.
- Do not attempt to extend the RJ-11 leads on CTid enabled DC CTs. Instead, extend CAT 5 between the eGauge and the Sensor hub using the included coupler. Refer to Sensor hub documentation for more details.