Current sensor: Single channel CT clamp (V3)

 

Product description

The Pressac sensing V3 wireless single channel CT clamp is designed to measure and report the AC current flowing in a single channel. Powered from the measured conductor, the measured current in the channel is reported every 30 seconds. The Pressac sensing V3 wireless single channel CT clamp is easily installed with no disturbance to the measured conductors.

 

Key features and benefits

  • Requires no interruption to electrical supply.
  • Pluggable CT clamps for easy feeding of wires.
  • Easy installation (simply clip around a single conductor only).
  • Knows what devices or appliances are switched on, and their energy usage.
  • Uses proven wireless technology.
  • No batteries, inductively powered.
  • Fully EnOcean compliant.

Available variants

Frequency Measurement Range Frequency Type Part Number
868MHz 1A – 60A (50Hz or 60Hz) EnOcean for Europe CTV3_868_1CH_060A
868MHz 2A – 200A (50Hz or 60Hz) EnOcean for Europe CTV3_868_1CH_200A
902MHz 1A – 60A (50Hz or 60Hz) EnOcean for USA/Canada CTV3_902_1CH_060A
902MHz 2A – 200A (50Hz or 60Hz) EnOcean for USA/Canada CTV3_902_1CH_200A
928MHz 1A – 60A (50Hz or 60Hz) EnOcean for Japan CTV3_928_1CH_060A
928MHz 1A - 200A (50Hz or 60Hz) EnOcean for Japan CTV3_928_1CH-200A

Commissioning

Pressac sensing V3 CT clamp RJ11 leads must be securely connected to the sender units RJ11 sockets. Channel numbers are printed on the product label on the sender unit.

CT_clamp_single-1

The clamp needs to be commissioned before use. There are two ways in which you can do this.

Self-powered learn
As the unit is 100% energy harvesting, it can only perform a self-powered learn if it is clipped around a conductor and the minimum required current is flowing. (See below table)

Single Channel CT Clamp V3 Versions Frequency Minimum Current Required For Commissioning and Reporting Current Reading Cap
60A version 868MHz
902MHz
928MHz
1A flowing 65A
200A version 868MHz
902MHz
928MHz
2A flowing 210A

Clip the CT clamp around the conductor and wait for 30 seconds. Depress the learn button, which is on the sender unit. The LED should briefly flash. The clamp is now commissioned.

Steps

  1. Ensure your sensor is powered and within range of your EnOcean gateway or receiving device.
  2. Place your EnOcean gateway or receiving device into inclusion mode.
  3. Press the learn button on the front of the sensor, the LED will blink RED. The device will now transmit a teach in telegram. CT Clamp receiver illustration
  4. Wait for the teach in process to end. Please allow extra time if using secure mode.
  5.  Successful inclusion will be indicated on the EnOcean gateway or receiving device.

Manual registration

Alternatively, the unit can be commissioned onto your EnOcean network manually. To do this you will need the unique EnOcean ID of the clamp and also its EnOcean Equipment Profile (EEP). The EnOcean ID and the EnOcean Equipment Profile (EEP) are printed on the product label.

To be able to measure the current flowing within a single conductor, the clamp must be correctly clipped around the single conductor, ensuring that the ferrite cores within the clamp reliably and consistently touch each other. In permanent installations, the unit can be cable tied to the conductor for added security.

Once installed and commissioned, the value of electric current is transmitted every 30 seconds. If a current lower than the minimum current required (see above table) is flowing, the Pressac sensing V3 CT clamp will not report any information or transmit any EnOcean telegrams.

The product uses an EnOcean STM300 Module for transmitting the data wirelessly. It supports the following EEPs (EnOcean Equipment Profiles): EEP D2-32-00.

Maintenance

The features that are of utmost importance to maintain within the lifespan of this product are the ferrite cores. It is important that the surfaces of each side of the ferrite cores are kept clean (which you can do using the alcohol wipes supplied), so that when the unit is clipped around a cable, the ferrite cores are touching each other. Failure of the surfaces to mate will cause incorrect readings to be measured and reported.

If the product appears to be malfunctioning, contact your dealer, or Pressac.

Technical specification

Measurement range 1A-60A ; 2A-200A
Measurement frequency 50Hz or 60Hz
Accuracy – whichever is greater 60A = +/- 0.1A or 2%
200A =  +/- 0.1A or 2%
Transmission rate 30 seconds
Reported value Channel 1 in Amps
Repeater No
Environment IP4X
Enclosure material Nylon 66
Sample time Average of five measurements per 30 seconds
Telegram VLD
Calibration Not required
Operating temperature & humidity range -5°C to +40°C; 0%-85% RH
Storage temperature & humidity range -20°C to +55°C; 0%-85% RH
Diameter of measurable conductor 60A – 10mm or less
200A – 24mm or less
Dimensions of clamp approx 60A – 25mm x 22mm x 35mm approx.
200A – 35mm x 45mm x 65mm approx.
Dimensions of case approx 80mm x 55mm x 20mm approx.
EEP D2-32-00

FAQ and troubleshooting

What is the range of the CT clamps?

This sensor communicates via the EnOcean protocol and has a maximum range of 30 metres. Please refer to the EnOcean wireless guidelines for further details.

How frequently do the CT clamps take samples?

Measurements are taken every five seconds and these values are collated to produce an average once every 30 seconds. This average figure is the transmitted value.

Is the transmitted measurement a total for all three channels, or are the values transmitted independently?

Measurements of all three channels are taken separately, these separate readings are transmitted in one EnOcean Telegram every 30 seconds.

How frequently is data transmitted?

An EnOcean Telegram containing the current readings for each channel will be sent every 30 seconds.

How do you calculate power consumption?

Current measurements will be taken within the measured conductor. To calculate the power consumption, additional voltage measurements and circuit power factor values (not provided by this product) will be required.

Can current be measured at appliance level?

The current can be measured at appliance level if there is a suitable place for the installation of the CT.

The lowest operating currents are as follows:

  • 60A Sensor – 1 Amp
  • 200A Sensor – 2 Amps

Can the sensor measure voltage?

This product only measures current within the measured conductor.

What is the accuracy per measurement channel?

Whichever is greater:

  • 60A sensor ± 0.1A or 2%
  • 200A sensor ± 0.1A or 2.5%

Can the leads be extended?

We recommend that extension leads are not used as the increase in resistance (Ohms) can affect the accuracy of measurements. Use of third-party leads will void the warranty of the sensor.

What is the EnOcean Equipment Profile (EEP) for the CT clamps?

  • 1 channel – D2-32-00
  • 3 channel – D2-32-02

Our system needs to receive the current RMS, can your product support this?

Yes our V3 CT clamps provide current RMS values.

Declaration of conformity

Download product datasheet