curremt transformer 1

[xuxu]

hi everyone...

what will happen if i connect a current transformer of ratio 600/5 in a line that the full load current is 150 Amp?

and what will happen in case of full load current is 600 Amps and CT is 150/5?

Regars

xuxu

 

[ScottyUK]

1) You will get 250mA of secondary current

2) In theory you would get 4A of secondary current. In practice and depending on what the specification of the CT is: possibly core saturation; possibly damage to the secondary winding; possibly both. With a low enough burden and a generously designed CT, possibly nothing untoward would happen.


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If we learn from our mistakes I'm getting a great education!

 

[oldfieldguy]

Scotty--

He said 600/5. 150 amps in = 1.25 amps out.

For 600 amps in a 150/5, the secondary current is is 20 amps. Okay for short time, but not continuous duty, assuming, as you said, you don't get into saturation problems.

old field guy

 

[scottf]

For 600A into a 150:5A CT, the impact depends on the rating factor of the unit. In the US, it's quite common to see RF 4.0 for metering CTs at this ratio.

If the RF is less than 4.0, then you run the risk of damaging the CT thermally if left continuously.

 

[ScottyUK]

OFG,

Maths was never my strong point. Not at work anyway...


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If we learn from our mistakes I'm getting a great education!

 

[price2008]

Price2008

1. If you connect a current x'mer with 600/5 ctr in a
150 amps load, then you will get two readings.
a.1.25 amps when reading is taken in the secondary
winding leads.And
b.250ma when reading is taken from the 5amps relay.
2. And for 600amps in a 150/5 ctr, as OFG said, you will get
20amps.of secondary current and 4amps when reading is taken from a 5amps relay.
hope this helps.