100A NON-INVASIVE AC CURRENT SENSOR SCT-013-000

100A NON-INVASIVE AC CURRENT SENSOR is a  i.e. it is a current transformer which can be used to measure AC current up to 100 amperes. Current transformers (CTs) are sensors that are used for measuring alternating current.

They, 100A NON-INVASIVE AC CURRENT SENSOR are particularly useful for measuring whole building electricity consumption (or generation for that matter).

The split core type such as the SCT-013-000 CT in the picture, is particularly suitable for DIY use it can be clipped straight on to either the live or neutral wire coming into the building without having to do any high voltage electrical work.

Like any other transformer, a current transformer has a primary winding, a magnetic core, and a secondary winding.

In the case of whole building monitoring the primary is the live or the neutral wire (not both) coming into the building itself and goes through the hole in the CT. The secondary winding comprises many turns of fine wire housed within the casing of the transformer.

Features

Core Material: Ferrite
External Material : ABS
Input Current : 100A
Frequency: 50HZ-150KHZ
Opening Size: 13 x 13mm/ 0.5″ x 0.5″(L*W)
Output Plug 3.5mm
Dielectric Strength 6000V AC/1min
Working Temperature -25-70°C
Cable Length : Approx. 1.18m/ 45.4″
Total Size : Approx. 60 x 30 x 20 mm

Applications of 100A Non Invasive AC Current Sensor

• Home Automation and Control applications where Current measurement is needed.
• Suitable for the current measuring
• Monitoring and protection of AC motor
• Lighting equipment
• Air compressor

Technical Specifications 100A Non Invasive AC Current Sensor

• Input Current: 0~100A AC
• Output Mode: 0~50mA
• Non-linearity: ±3%
• Turn Ratio: 100A:0.05A
• Resistance Grade: Grade B
• Work Temperature: -25°C ~ ﹢70°C
• Dielectric Strength(between shell and output): 1000V AC/1min 5mA
• Leading Wire in Length: 1m
• Open Size: 13mm x 13mm

100A Non Invasive AC Current Sensor  – Interfacing with an Arduino

To connect 100A NON-INVASIVE AC CURRENT SENSOR to an Arduino, the output signal from the 100A NON-INVASIVE AC CURRENT SENSOR needs to be conditioned so it meets the input requirements of the Arduino analog inputs, i.e. a positive voltage between 0V and the ADC reference voltage.

Note: This page give the example of an Arduino board working at 5 V and of the EmonTx working at 3.3 V. Make sure you use the right supply voltage and bias voltage in your calculations that correspond to your setup.

This can achieve with the following circuit which consists of two main parts:

1. The CT sensor and burden resistor
2. The biasing voltage divider (R1 & R2)

Calculating a Suitable Burden Resistor Size

If the CT sensor is a “current output” type such as the 100A NON-INVASIVE AC CURRENT SENSOR, the current signal needs to be converted to a voltage signal with a burden resistor. If it is a voltage output CT you can skip this step and leave out the burden resistor, as the burden resistor is built into the CT.

a) Choose the current range you want to measure

The 100A NON-INVASIVE AC CURRENT SENSOR has a current range of 0 to 100 A. For this example, let’s choose 100 A as our maximum current.

b) Convert maximum RMS current to peak-current by multiplying by √2.

Primary peak-current = RMS current × √2 = 100 A × 1.414 = 141.4A

c) Divide the peak-current by the number of turns in the CT to give the peak-current in the secondary coil.

The 100A NON-INVASIVE AC CURRENT SENSOR has 2000 turns, so the secondary peak current will be:

Secondary peak-current = Primary peak-current / no. of turns = 141.4 A / 2000 = 0.0707A

d) To maximize measurement resolution, the voltage across the burden resistor at peak-current should be equal to one-half of the Arduino analog reference voltage. (AREF / 2)

100A NON-INVASIVE AC CURRENT SENSOR

If you’re using an Arduino running at 5V: AREF / 2 will be 2.5 Volts. So the ideal burden resistance will be:

Ideal burden resistance = (AREF/2) / Secondary peak-current = 2.5 V / 0.0707 A = 35.4 Ω

35 Ω is not a common resistor value. The nearest values either side of 35 Ω are 39 and 33 Ω. Always choose the smaller value, or the maximum load current will create a voltage higher than AREF. We recommend a 33 Ω ±1% burden. In some cases, using 2 resistors in series will be closer to the ideal burden value. The further from ideal the value is, the lower the accuracy will be.

Here are the same calculations as above in a more compact form:

Burden Resistor (ohms) = (AREF * CT TURNS) / (2√2 * max primary current)

Burden resistor sizing for OpenEnergyMonitor energy monitoring hardware.

emonTx V3 (see guide)

The emonTx V3 uses a 3.3V regulator, so it’s V_CC and therefore AREF, will always be 3.3V regardless of battery voltage. The standard emonTx V3 uses 22Ω burden resistors for CT 1, 2 and 3, and a 120Ω resistor for CT4, the high sensitivity channel. See the emonTx V3 technical wiki at: https://wiki.openenergymonitor.org/index.php?title=EmonTx_V3#Burden_Resistor_Calculations.

emonPi (see guide)

The EmonPi has two CT channels both with 22Ω burden resistors.

emonTx V2

If you’re using a battery powered emonTx V2, AREF will start at 3.3 V and slowly decrease as the battery voltage drops to 2.7 V. The ideal burden resistance for the minimum voltage would therefore be:

Ideal burden resistance = (AREF/2) / Secondary peak-current = 1.35V / 0.0707A = 19.1 Ω

19 Ω is not a common value. We have a choice of 18 or 22 Ω. We recommend using an 18 Ω ±1% burden.

Package:-

1 x 100A NON-INVASIVE AC CURRENT SENSOR

Related Products at majju.pk

SCT 013 100A Non-Invasive AC Current Sensor Split Core Type Clamp Meter Sensor
SCT013-000 CT 100A Noninvasive AC Current Sensor