Frequently Asked: Difference between revisions
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Make sure the SCT is clamped around A SINGLE PHASE. | Make sure the SCT is clamped around A SINGLE PHASE. | ||
Clamping the SCT on the whole cable will never read anything as it | Clamping the SCT on the whole cable will never read anything as it measures two currents. One positive minus plus one negative which sums to 0 (or 0 + noise). | ||
The easiest for a quick test is to connect the SCT at the meter level on a single phase. Otherwise if you wish to measure the power used by a single application then one should make a special cable that split phases. | The easiest for a quick test is to connect the SCT at the meter level on a single phase. Otherwise if you wish to measure the power used by a single application then one should make a special cable that split phases. | ||
Revision as of 20:35, 23 September 2017
Why am I not reading zero when the SCT is not connected
The SCT sensor is an analog sensor and hence has a background noise. i.e. It will never read the exact measured value.
Even if nothing is connected there will be always a tiny current running in the burden resistor inducing a small voltage. In turn this will convert into a small power. For a board setup for the SCT-013-000 one might find a background noise under 100W.
This is normal!
I can not read anything once the CT is clamped
Make sure the SCT is clamped around A SINGLE PHASE.
Clamping the SCT on the whole cable will never read anything as it measures two currents. One positive minus plus one negative which sums to 0 (or 0 + noise).
The easiest for a quick test is to connect the SCT at the meter level on a single phase. Otherwise if you wish to measure the power used by a single application then one should make a special cable that split phases.