Instructions CT-1/CT-2 Current Transformer 070-7957-01
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General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. To avoid potential hazards, use this product only as specified. To Avoid Fire or Personal Injury Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings and markings on the product. Consult the product manual for further ratings information before making connections to the product. Do Not Operate With Suspected Failures.
General Safety Summary ii CT-1/CT-2 Current Transformer
Introduction The CT-1 and CT-2 are high-frequency, bidirectional current probes. The CT-1 is a 1 GHz current probe and the CT-2 is a 200 MHz current probe. Each current probe comes with a P6041 probe cable to allow you to connect directly to an oscilloscope to make measurements. Earth ground mounting stud P6041 Probe connection Figure 1: CT-1 current probe The CT-1 and CT-2 are available as separately purchased units (Option 09).
Description The CT-1 (1 GHz) and CT-2 (200 MHz) are current probes designed for either permanent or temporary installation in the device-under-test (DUT). These probes are particularly useful for measuring high-frequency currents in solid state circuitry with minimum circuit loading. Due to bidirectional compatibility, the CT-1 and CT-2 can be used to inject a signal or as an interstage transformer. The probes inductively measure current through a conductor and develop a voltage proportional to the current.
Description 0 ADC 0.5 ADC 1 ADC 100% 90% 80% 70% 60% 1k 10 k 100 k 1M Frequency (Hz) 10 M 100 M This response was obtained with the + side of the CT-2 facing the signal source (preferred connection) Figure 3: CT-2 frequency response vs. DC current The CT-1 and CT-2 consist of a current transformer and a flexible probe cable that attaches between the transformer and the oscilloscope.
Specifications Table 1 lists the electrical characteristics of the CT-1 and CT-2 Transformers when they are connected to the P6041 Probe cable. The environmental and physical characteristics follow Tables 1 and 2. Table 1: Electrical characteristics Specification CT-1 with P6041 Probe CT-2 with P6041 Probe Sensitivity (see Figures 2 and 3) 5 mV/mA, ±3% into a 50 W load 1 mV/mA, ±3% into a 50 W load Pulse Response Rise time: < 0.35 ns, 10% to 90% Rise time: < 0.
Specifications Table 2: General specifications (CT-1 and CT-2) Environmental Meets all Class IV instrument specifications Operating Temperature 0_ C to +55_ C Nonoperating Temperature –62_ C to +82_ C Mechanical Hole size: CT-1 1.78 mm (0.070 in.) CT-2 1.32 mm (0.052 in.) Dimensions 6-32 mounting stud Connector 15 mm (0.59 in.) 38.6 mm (1.52 in.) P6041 Probe cable length 106.68 mm (42 in.) Weight 15 gm (0.525 oz.) without P6041 10.3 mm (0.406 in.) 47 gm (1.655 oz.
Operation This section describes how to install the CT-1 or CT-2, discusses low-frequency probing, and provides information on safety and product care. Installing the CT-1 or CT-2 The CT-1 or CT-2 transformers can be attached to the chassis or circuit board to measure current in transistors, diodes, or other components. Any number of transformers can be used. When observing the output of a CT-1 or CT-2 transformer, ensure it is terminated into 50 W.
Operation Low Frequency Response The low-frequency response of the current transformer is proportional to the inductance of the transformer windings. A DC component in the current being measured tends to reduce this inductance. Figures 2 and 3 show this effect in the frequency domain. This effect is also seen in the time domain. Figure 6 shows that the pulse tilt is increased in the presence of significant DC current. The DC current required to increase the tilt by a factor of two is about 0.3 A.
Operation 0 ADC 10 mA/div 5 ms/div 0.4 ADC Input current Output voltage 0.4 ADC 0 ADC Figure 7: CT-2 decay characteristics referenced to transition Additional consideration needs to be given to the amp second rating of the transformer. The product of the pulse current and the pulse duration should be less than the amp second rating to keep the transformer core from saturating. When saturation occurs, the output voltage falls to zero.
Replaceable Parts List This section contains a list of the replaceable parts for the CT-1 and CT-2. Use this list to identify and order replacement parts. Parts Ordering Information Replacement parts are available through your local Tektronix field office or representative. Changes to Tektronix products are sometimes made to accommodate improved components as they become available and to give you the benefit of the latest improvements.
Replaceable Parts List Parts list column descriptions Column Column name Description 1 Figure & index number Items in this section are referenced by figure and index numbers to the exploded view illustrations that follow. 2 Tektronix part number Use this part number when ordering replacement parts from Tektronix. 3 and 4 Serial number Column three indicates the serial number at which the part was first effective. Column four indicates the serial number at which the part was discontinued.
Replaceable Parts List 2 1 4 3 Recommended accessories Figure 8: CT-1 and CT-2 accessories Replaceable parts list Fig. & index number Tektronix part number Serial no. effective Serial no. discont’d Qty 8-1 Name & description Mfr. code CURRENT TRANSFORMER:CT-1 OR CT-2 WITH P6041 (OPION 09 W/O P6041) 8-2 Mfr. part number CT-1 OR CT-2 1 P6041 80009 P6041 24931 28A100–2 8-3 103–0028–00 1 ADAPTER,CONN:BNC,FEMALE TO FEMALE,1.
Replaceable Parts List 12 CT-1/CT-2 Current Transformer
