T: +44 1274 750 620

E: sales@ndmeter.co.uk

8am - 4:30pm Monday - Friday UK

Clamp-on Current Transformers, AC Current Transducers AC/DC Hall Effect Clamps, Injection Clamps
Download PDF
There are five basic types, with popular devices available ex-stock. All can be manufactured to customer’s exact specification. • AC Current Transformers AC Current Input – AC Current Output Current Transformers. Hand-held and openable. • AC Current Transducers AC Current Input – AC Voltage Output The widest range, optimised for modern electronic instruments • AC Current Transducers AC Current Input – DC Voltage Output Special models for Data Logging & Recording. • AC/DC Hall Effect Clamps AC/DC Current Input – AC/DC Voltage Output For DC and mixed AC plus DC measurement Traditional Current Transformers manufactured as a Clamp-on device for portable applications. Ideal for use with electronic kWh Meters or other devices with an AC Current input. Frequency range extends from 45Hz to beyond 5kHz. Medium & Large Models are available with 1 Amp, 5 Amp & other outputs, and with single or 3 range primaries. M series mini Clip-on CTs are not available with 5 Amp output. Open circuit protection available on 1 Amp models. Medium and Large Models are also available with a combined Current & Voltage Output. A Hall Effect cell is mounted within the magnetic circuit of the Clamp-on CT, and the necessary conditioning electronics within the handle. This range of Clamp-on CTs provides an output which is a direct image of the current from DC to 1kHz (or even higher for some models). .1C models are for OEM use and require an external DC power supply, and are supplied to customer specified input & outputs. .2C and .3C are powered by an integral battery. The Large battery powered models are all dual range With an integral AC → DC transducer. By including an AC to DC converter transducer within the clamp-on CT, and powering the electronics from the measured current, this range of Clamp-on CTs is ideal for use with Data Loggers, Chart Recorders, Computer Data Acquisition Systems, etc - in fact any equipment which has a DC Voltage input and needs to monitor and/or log current trends. Identified as xx.D (1 range) or xx.3D (3 range). xx.DM are designed for lower currents. By providing a AC Voltage Output, the Clamp-on CT becomes inherently open circuit protected. A 1 Volt (or even better 100mV) output allows the clamp to operate under optimum conditions. On Medium and Large models, the .UE is the basic device, single range only and normally with a 1 Volt output. .U are improved models with outputs up to 5 Volt, and are available as single or 3 range devices. By standardising on a 1 Volt AC output (or even less) from a Clamp-on CT, the user is assured of the widest range of full scale input currents - from 1 Amp to 3000 Amp. Identified as xx.U or xx.UE; also available as xx.UM versions for low current measurement. xx.3U etc is a 3 range device, switch selectable. • Injection Clamps Instead of measuring a current, clamp-on CTs can be used to inject a signal into an external conductor. Applications include tracing cables or pipework, identifying individual cables, etc. All models can be supplied with custom windings for this application.
AC Current Output
AC Voltage Output
DC Voltage Output
Hall Effect AC/DC
Popular and readily available models Small M1, M2, M3 & M4 Medium US, S & SM Large E, H & P M1 200A:200mA M1 100A:1A M1 200A:1A M1.M 100A:100mA M1.M 10A:2mA M1.U 100A:0.1V M1.U 100A:1V M1.U 200A:2V M2.D 100A:1V M2.DM 25A:1V M2.DM 100A:1V S 1000A:1A S 1000A:5A S 1200A:1A S 1200A:5A SM 1000A:1A SM 1000A:5A US.U 1000A:1V US.U 1000A:5V US.UE 1000A:1V US.3D 25,50,100A:1V US.3D 250,500,1000A:1V S.3D 25,50,100A:1V S.3D 250,500,1000A:1V S.1C OEM Model From 200A:1V to 1500A:11/2V S.2C From 100A:1V to 800A:800mV S.3C 1000A:1V or 100A, 1000A:1V S.C 2000A:2V or 200A, 2000A:2V US 1000A:1A US 1000A:5A E16 1000A:1A E16 1500A:1A E32 2000A:1A E32 3000A:1A H16 1000A:1A H16 1500A:1A H32 2000A:1A H32 3000A:1A P16 1000A:1A P16 1500A:1A P32 2000A:1A P32 3000A:1A Also available with 5 Amp output M1.UM 1A:1V M1.UM 5A:1V M1.UM 20A:1V M1.UM 50A:1V All AC voltage output models are also available as 3 Range versions Identified as xx.U3 or xx.UE3. S.U 1000A:1V S.UE 1000A:1V S.UM 1A:1V S.UM 25A:1V SM.U 1000A:1V SM.UE 1000A:1V SM.UM 1A:1V SM.UM 25A:1V E16.U 1000A:1V E16.U 1500A:5V E16.UE 1500A:11/2V E32.U 3000A:1V E32.U 3000A:5V E32.UE 3000A:1V H16.U 100A:1V H16.U 1500A:1V H16.UE 1500A:11/2V H32.U 3000A:1V H32.U 3000A:5V H32.UE 3000A:1V P32.U 3000A:1V P32.U 3000A:1V P32.UE 3000A:1V P16.U 1000A:1V P16.U 1500A:1V P16.UE 1500A:11/2V E16.3D 250,500,1000A:1V E16.3D 500,1000,1500A:1V E32.3D 500,1000,1500A:1V E32.3D 1000,2000,3000A:1V Also available as H and P models for larger sizes. Small clamp-on CTs are NOT Available H20.3C xxx,2000A:2V H40.3C xxx,4000A:2V H50.3C xxx,5000A:2V P20.3C xxx,2000A:2V P40.3C xxx,4000A:2V P50.3C xxx,5000A:2V P75.3C xxx,7500A:2V Also available as single range .1C OEM models
A very wide range of alternative inputs and outputs are available for all the above models
Clamp-on CTs are compact hand-held devices offering non-contact current measurement for all types of portable instrumentation, including DMMs, Oscilloscopes and all types of recorders and analysers. Full detailed specifications are available on request for any variation. Selecting Clamps
Small – to 300 Amp M2 & M4 have a slightly larger case, allowing space for switches (for range changing) or for internal electronics. M3 & M4 are specifically designed to allow use on un-insulated cables at voltages up to 600 volt to ground. Medium – to 1200 Amp The S series is recommended for general purpose measurement on currents up to 1200 Amp. The SM series is recommended for high accuracy applications. Large – to 3000 Amp E16, H16 & P16 are recommended for the measurement of currents up to 1500 Amp. For higher currents up to 3000 Amp, the E32, H32 & P32 should be used. OEM Applications All clamps can be supplied customised for OEM applications. Options include winding ratios & output signals, output connection, case colour, etc. A technical advice service is available to allow manufacturers obtain the maximum performance from any clamp model or range of models. Hall Effect Clamps Hall Effect Clamps are available in 2 different forms: As a battery powered unit for use with multimeters, oscilloscopes, etc. These would normally be fitted with 4mm safety sockets for output. The SC is available as a single or dual range device, the H & P models are dual range as standard. As an externally powered unit for OEM use. Input range and output signal can be specified. Although specifically designed for use on DC systems, their frequency response extends to 10 kHz for certain models. Frequency Range All AC clamps are designed for use on AC power circuits and, with a few exceptions, are suitable for measurement of harmonics up to 5 kHz or 10 kHz. For measurement of high frequency signals, the maximum current will need to be reduced to prevent excessive heating and, where the output is a current, the burden reduced in proportion to the frequency increase. Safety All clamp-on CTs fully comply with the relevant safety standards. Maximum operating voltages depend on the model being used and are detailed in the individual specifications. Accuracy Clamp-on CTs are designed for portable use. They are much less affected by stray magnetic fields (from adjacent conductors) than Rogowski flexible current sensors. The larger models (SM, E, H & P) offer Class 0.5 accuracy at higher currents, with the highest accuracy available from the SM which has been specially designed for such applications. Output Connections Standard output connection for all AC clamp-on CTs is by 4mm safety sockets. At request, clamps can be supplied with captive cables – either unterminated or with a connector fitted. Standard connectors include 4mm Safety Plugs. Size & Weight See Brochure For Full Size & Weight Graph.
Site Products Contact
Home About Contact
Rail Mounted Meters Panel Mounted Meters Wall Mounted Meters
MMU's Currents Transformers Transducers
Clamp On Current Transformers
+44 1274 750 620 sales@ndmeter.co.uk 8am - 4:30pm Monday - Friday