Why CT secondary should not be kept open?
Answer Posted / iamdon
The CT secondary should not be left opened secondary due to
following reasons:
1)Zero current in secondary leads zero back emf.So primary
current becomes very high as the primary resistance is very
low.Large heat generated may burn the winding and core.If
the transformer sustain this heat, even then its operation
becomes improper as explained below.
2)CT is bascially a step up transformer.So high voltage
induced in secondary may saturate the core (core becomes
permanently damaged).So the operating point advances in non
linear region,which makes the transformer operation improper
(secomdary current will not replicate the primary according
to the turn ratio).
3)High voltage spikes(order of kV) produced in secondary side
may endanger the life of personnel working on the secondary
side.
4)High voltage spikes(order of kV) produced in secondary side
is sufficient to break down the transformer insulation.
Author:arbelectbit@yahoo.com
Is This Answer Correct ? | 30 Yes | 19 No |
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