YHDC SCT010 added to tables

A user has sent in a pair of YHDC SCT010 current transformers for evaluation and incorporation into the data tables. This is a smallish 50A:50mA split core CT. They arrived with 50cm leads and no connection jack. They have TVS diodes.

Comparing size with other available 50A CTs, they are about the same size as the Echun ECS1050 and somewhat smaller than the AcuCT-H040-50.

Measuring phase correction, they seem to work full range at both 60Hz and 50Hz, but are on the edge at 50Hz. This is with the 20 Ohm IoTaWatt burden resistor. They would probably perform better with the recommended 10 Ohm burden.

For comparison, here is the phase correction curves for ECS1050 and AcuCT-H040-50:

The SCT010 is well behaved up to about 35 Amps, then begins to climb sharply, especially at 50Hz, indicating that is struggling to produce the VA needed to push against the 20 Ohm burden. This is no big surprise. The SCT-006 has the same issue.

On balance, this CT should give good results up to about 40Amps primary.

The tables will be updated shortly to include the SCT010.


Thanks Bob,
I spotted that my IoTaWatt had restarted yesterday morning which is very unusual as it’s been rock solid since I found that the Kasa app may (haven’t seen it with the latest app update) still reboot IoTaWatt with its malformed mDNS packets (Malformed mDNS packet causing reboot).

Anyway, I found in the Message Log that you’d already updated the CT tables to include the SCT010 and duly updated my Inputs:

8/24/22 06:03:30z Updater: update tables from 0.0.5 to 0.0.6
8/26/22 10:30:02z timeSync: Six week routine restart.

Thanks again,

1 Like

Yes, I can push updated tables to the installed base. The routine six week restart is a simple way to insure that there would be no issue with rollover of the internal millisecond clock.