Potentiometer and Instrument Transformers · Electrical and Electronics Measurement · GATE EE
Marks 1
1
The table lists two instrument transformers and their features:
| Instrument Transformers | Features |
|---|---|
| X) Current Transformer (CT) | P) Primary is connected in parallel to the grid |
| Y) Potential Transformer (PT) | Q) Open circuited secondary is not desirable |
| R) Primary current is the line current | |
| S) Secondary burden affects the primary current |
The correct matching of the two columns is
GATE EE 2024
2
Instrument transformers are known to introduce magnitude and phase errors in measurements. These are primarily due to
GATE EE 2000
3
A potentiometer is basically
GATE EE 1997
4
A transfer instrument employed in the standardization of a polar type $$a.c$$ potentiometer is ______
GATE EE 1997
5
The primary current in a current transformer is dictated by
GATE EE 1997
6
In $$d.c.$$ potentiometer measurements, a second reading is often taken after reversing the polarities of the $$s.c.$$ supply and the unknown voltage, and the average of the two readings is taken. This is, with a view to eliminate the effects of
GATE EE 1992
Marks 2
1
A $$200/1$$ current transformer $$(CT)$$ is wound with $$200$$ turns on the secondary on a toroidal core. When it carries a current of $$160$$ $$A$$ on the primary, the ratio and phase errors of the $$CT$$ are found to be $$-$$ $$50$$% and $$30$$ minutes respectively. If the number of secondary turns is reduced by $$1$$ the new ratio error (%) and phase error (min) will be respectively.
GATE EE 2006
2
A $$50$$ $$Hz,$$ bar primary $$CT$$ has a secondary with $$500$$ turns. The secondary supplies $$5A$$ current into a purely resistive burden of $$1\,\Omega $$. The magnetizing ampere-turns is $$200$$. The phase angle between the primary and secondary current is
GATE EE 2004
3
The core flux in the $$CT$$ of above problem under the given operating condition is
GATE EE 2004
4
A $$500$$ $$A/5$$ $$A,$$ $$50$$ $$Hz$$ current transformer has a bar primary. The secondary burden is a pure resistance of $$1\,\Omega $$ and it draws a current of $$5A$$. If the magnetic core requires $$250$$ AT for magnetization, the percentage ratio error is
GATE EE 2003
5
A d.c. potentiometer is designed to measure up to about $$2$$ $$V$$ with a slide wire of $$800$$ mm. A standard cell of emf $$1.18V$$ obtains balance at $$600$$ mm. A test cell is seen to obtain balance at $$680$$ mm. The emf of the test cell is
GATE EE 1994