AC meters and AC Current Transformer Rings

Name of the lesson

Purpose of the lesson

During this lesson, you will learn how to choose the correct AC meter and current transformer ring for your site

Target Audience

Service providers, back-office, organization managers, technicians, etc.

What to expect at the end of the lesson

The user will acknowledge:

Which AC meters and Current Transformer Rings does Galooli provide
Which AC meters are suitable for which Current Transformer Rings
How to choose the perfect AC Meter and Current Transformer Ring for my site
How accurate are the AC Meter and the AC ring
How to install the AC meters and Current Transformer Rings on site

It is highly recommended to go through the contents in the order in which they appear

Which AC meters and Current Transformer Rings does Galooli provide?

Galooli supports a variety of AC meters and Current Transformer Rings according to the changing needs of the users, different currents, amount of phases, conversion ratio, and the diameter of the AC cables.

The meters can include an entry for the AC cable or meters that require the use of Current Transformer Rings.

Current Transformer Rings can be used with cables of varying diameters, some of which have an open and close mechanism.

AC Current Transformer Rings:

Which AC meters are suitable for which Current Transformer Rings?

AC meter works without any Current Transformer Ring however, the cable entry
can be too narrow for some cable's diameter.

AC meter works best with therings. Specifically with the rings that has a conversion ratio of 1A.

AC meter works best with the rings.

How to choose the accurate AC Meter and Current Transformer Ring for my site?

There are a couple of questions you should answer to choose the most suitable AC Meter and Current Transformer Ring:

What is the current that needs to be measured?
How many phases does the energy source have?
What is the conversion ratio?
What is the diameter of a cable that needs to be measured?

The following table allows you to easily choose the required products.
Catalog numbers are internal to Galooli.

Ring Diameter/Current	≤ 30A	≤ 50A	≤ 150A	≤ 200A	≤ 4000A
≤ 11 mm	CE Transducer CE42 No Current Transformer Ring needed
≤ 24 mm	CE Transducer CE42CT + CE-CTH Split Core (24mm/30A)	CE Transducer CE42CT + CE-CTH Split Core (24mm/50A)	CE Transducer CE42CT + CE-CTH Split Core (24mm/150A)
≤ 36 mm	CE Transducer CE42CT + CE-CTH Split Core (36mm/30A)	CE Transducer CE42CT + CE-CTH Split Core (36mm/50A)	CE Transducer CE42CT + CE-CTH Split Core (36mm/150A)
≤ 350 mm	Carlo Gavazzi EM210 + Rogowski CT (350mm)
≤ 600 mm	Carlo Gavazzi EM210 + Rogowski CT (600mm)
≤ 900 mm	Carlo Gavazzi EM210 + Rogowski CT (900mm)

How accurate are the AC Meter and the AC ring?

Item Codes/Data	Meter Accuracy		Ring Accuracy	Accuracy Calculation

Item Codes/Data	Meter Accuracy		Ring Accuracy	Accuracy Calculation
Galooli Item Code	Voltage reading accuracy	Current reading accuracy	CT Accuracy	Overall voltage accuracy	*Overall current accuracy	*Overall kwh accuracy
CE Transducer CE42CT (Meter)	0.50%	0.50%	Not relevant
CE-CTH Split Core 24mm/30A (Ring)	0.50%	0.50%	1.00%	0.50%	1.50%	2.60%
CE-CTH Split Core 24mm/50A (Ring)	0.50%	0.50%	0.50%	0.50%	1.00%	2.10%
CE-CTH Split Core 24mm/150A (Ring)	0.50%	0.50%	0.50%	0.50%	1.00%	1.50%
CE-CTH Split Core 36mm/30A (Ring)	0.50%	0.50%	1.00%	0.50%	1.50%	2.60%
CE-CTH Split Core 36mm/50A (Ring)	0.50%	0.50%	0.50%	0.50%	1.00%	2.10%
CE-CTH Split Core 36mm/150A (Ring)	0.50%	0.50%	0.50%	0.50%	1.00%	1.50%
**CE Transducer CE42 (Meter)	0.50%	0.50%	Not relevant			1.00%
***400-AcRin150A5A-502 (Ring)	0.50%	0.50%	1.00%	0.50%	1.50%	2.00%
***400-AcRin50A5A-502 (Ring)	0.50%	0.50%	3.00%	0.50%	3.50%	4.00%

*Overall current accuracy = Meter current reading accuracy + CT Accuracy

*Overall kwh accuracy = Overall voltage accuracy + Overall current accuracy

**The meter can measure current and voltage without a CT ring

***These rings are not available for sale

Calculation Examples
In order to see the calculation method and ensure that the data for the units are correct for you, please
refer to the attached Excel file. You should download the Excel file to your computer.

What is the best way to install the AC meters and Current Transformer Rings on site?

The installation process of the AC Meter and Current Transformer Ring needs to be accurate and in the right order for the current measurement will be correct.

You will find a lot of important information about the AC Meter and Current Transformer Ring installation process in the “Read more” section.