Current transformer
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That type of current transformer is more reliable and is used to output 4-20mA
Is it a current transformer or a current transmitter?
Current transformer + current transmitter
Current transformers don’t seem to have this, right!
How much is needed, and where will it be used?
It should be that the current transformer first outputs a signal, which is then sent to the DCS via a current transmitter. A regular one will do; currently, there isn’t any integrated version available I think
CT generally outputs a standard signal of 0~5A; a transduction output is required, and a current transmitter of 0~5A / 4~20mA can be installed.
It should be noted that current transmitters generally have no problem handling currents of 0–5A, but in the event of faults such as short circuits, the current can exceed 5A. At such times, it is necessary to find out in advance whether the transmitter can withstand this surge current or whether it can accurately reflect such currents when placing an order.
Only through a current transmitter can 4–20mA be output
There are current transformers that output 4-20mA signals directly, but they are called current transmitters; they require an external 24V DC power supply and operate on a two-wire system, with the power supply and the output wires sharing the same conductor. The transformation ratio must be chosen by oneself. The primary current can be 100A, 150A, 200A, and so on.
Yes, I found it on an electrical equipment website before; the power supply can be 110VDC/AC or 220VAC, it has an impact current resistance of more than 7 times the normal value, the range ratio can be set, and it provides a 4–20MA transmission output. Go and check it out.
Are you referring to the transformer used before the current transmitter? In my opinion, it’s better to choose one with a larger capacity, as this has little impact on accuracy
I’m looking for DC ammeters with ranges of around 0–20A and 0–80A. Are there any standard products available? The error we are currently experiencing is quite large; there is a difference of 5 times compared to the digital meter. It should be noted that the primary side uses thyristors, the secondary side is measured by a DC meter, and a full bridge circuit with filtering is employed.
To measure direct current, a shunt is generally used (it has a certain DC resistance; when current flows through it, a certain voltage drop is generated. The direct current can be measured by detecting this voltage drop. Different shunts can be selected depending on the magnitude of the current, without the need to replace the measuring instrument). )
How can I accurately determine the actual total current when I only have a 10A digital meter? It’s very difficult to achieve accuracy by measuring the shunt resistance and similar methods; of course, it’s possible to use a gauge with a large measurement range for comparison as well. I just hope there are standard products that can be purchased and used right away.
There are 10A direct-type DC ammeters available; you can connect them in series within the DC circuit to carry out measurements. The shunts are all standard.
What was said upstairs makes sense, but the person who asked the question on the first floor didn’t clarify their question properly.
How much is a set for measuring DC current with a 100A Hall effect sensor? Should power be supplied? What is the accuracy, especially below 10A?