Wiki User
∙ 11y agoThe wattmeter will read downscale (backwards).
Wiki User
∙ 11y agoJust like reading a book. Left to right, up to down.
A current transformer has to have the same ratio as the meter that it drives. Full scale deflection on the meter is 5 amps which equals the maximum allowed current on the phase that it is reading. A different ratio on the CT to meter would show an erroneous reading on the meter depending on the ratio of the connected CT. To keep costs down the meter is common to all three phases and is read by connecting the meter to the phase CT through a three position switch.
These are used with low range ammeters to measure current in HVAC 's where direct connection of instruments is impratical. They not only insulate the instruments from HV lines but also step down current in a known ratio. ( i .e . ) Iline =(I1 \I2) * Ammeter Reading where Iline = Line Current I1 \I2 = Current Ratio
The clamp on amp meter has to go around both of the parallel conductors to get an accurate reading of the line current. If you are using a current transformer, both wires have to go through the centre hole in the transformer.
"Rated current" is the current the device (motor or transformer?) is designed to handle at full load. "Tripping current" is the current where a protective device (fuse, breaker) will open to protect the device from overload/overheating. "Tripped current", may be the current the tripping device measured prior to making the decision to trip, if you are reading this from a digital protective device like a relay or OCR.
This is a transformer built into electrical appliance to make electricity meter to stop reading or made to read in reverse order. This reduces the consumption reading and cheats the system. That is bad.
Just like reading a book. Left to right, up to down.
A current transformer has to have the same ratio as the meter that it drives. Full scale deflection on the meter is 5 amps which equals the maximum allowed current on the phase that it is reading. A different ratio on the CT to meter would show an erroneous reading on the meter depending on the ratio of the connected CT. To keep costs down the meter is common to all three phases and is read by connecting the meter to the phase CT through a three position switch.
Measuring currents to 100A A.C. You set the meter to 100 mA and connect the transformer output to the meter. When the primary current is connected the meter will read the current flow. Full scale (100mA) then means 100A in the transformer, so you multiply the scale reading by 1,000.
These are used with low range ammeters to measure current in HVAC 's where direct connection of instruments is impratical. They not only insulate the instruments from HV lines but also step down current in a known ratio. ( i .e . ) Iline =(I1 \I2) * Ammeter Reading where Iline = Line Current I1 \I2 = Current Ratio
The clamp on amp meter has to go around both of the parallel conductors to get an accurate reading of the line current. If you are using a current transformer, both wires have to go through the centre hole in the transformer.
From Reading, London is to the East.
If the resistor is removed from the circuit, the total resistance in the circuit decreases. This causes the total current in the circuit to increase, which would result in an increase in the ammeter reading.
"Rated current" is the current the device (motor or transformer?) is designed to handle at full load. "Tripping current" is the current where a protective device (fuse, breaker) will open to protect the device from overload/overheating. "Tripped current", may be the current the tripping device measured prior to making the decision to trip, if you are reading this from a digital protective device like a relay or OCR.
Yes; that is the principle used in no-load tests on transformers. The current in the copper windings is zero on the secondary and low on the primary, so the copper loss is negligible.
The idea is that the magnetic field of the device reacts with the external magnetic field. If the current is reversed, the magnetic field would also be reversed, and the reading would be the opposite.
Don't check transformer windings with an ohmmeter. All you can do is determine if there's a break in the wiring. If it's reading as "open", then you know that the transformer is broken. It is not repairable without a considerable effort. I'm curious as to how you obtained that transformer. It's quite dangerous and you shouldn't play with it unless you know what you're doing. You are likely to be killed if you try to power it up. DO NOT try to use this in a prank. There are lethal consequences.