When testing grounding electrodes on the two wire path of a. Clamp meters using current transformer for ac measurement current transformer clamp meters are equipped with rigid jaws of made of ferrite iron. Using a clampon tester to test ground resistance important. It has very low impedance because it must have very low amount of voltage drop across it an. What i have in mind is that wire creates the changing flux that induces voltage in the meter. When it is not in use for a long time, please remove the battery and avoid storing it in the place with high temperature and humidity. Basic theory of clamp meter to measure rms of current wave. Pdf a measurement technique to calibrate current clamp meters in ac current in the measurement range. The measured current value when the clamp meter is applied around both wires at the same time is the leakage current. Clampon flow meters from micronics are noninvasive with no interruption to your process. So, although the ground system had low earth ground resistance values when initially installed. Clamp meters are widely used by electricians in order to measure very high currents with the help of a transformer. It gets rid of the unnecessary procedure of breaking the circuit to measure current. Ceesi measurement services garner, iowa this paper is aimed at ultrasonic natural gas meters that use transit time across the gas pipe as the measurement variable.
A digital clamp meter is a device that measures current in amperes a by magnetic induction. The replacement must be test leads in good working condition with the same or equivalent rating. Clamp meter safety information 3 remove the test leads from the meter before the battery door is opened. Since some states or countries do not allow the exclusion or. Cm240 digital clamp meter is a 1 3 2 digit lcd multi meter with steady operations, fashionable structure and highly reliable measuring instrument. Custody transfer meters using sensors wetted with gas are the more familiar meter format. Using the clamp meter be44 you can easily check the amperage of alternating an direct currents, ac and dc voltages, resistances, the power frequency or the. Jun 05, 2016 ammeter means amperemeter which measures current. In contrast to a multi meter, the clamp meter does not need to be connected to the circuit in order to read current.
Current transformer clamp meters are equipped with rigid jaws of made of ferrite iron. Transformer jaws o trigger i data hold switch o rotary switch. The meter has clamp head frequency measurement function. It enables systematic pricing of energy consumed by individual consumer as it measures the amount of electrical energy consumed by a residence, business, or. The main principle of ammeter is that it must have a very low resistance and also inductive reactance. How does a clamp meter work, how does a dc clampmeter work. Clamp meters working principle instrumentation tools.
It is often very difficult to measure the current directly, since the value of the current is too large to apply it directly to the meter circuit, or simply because it. In electrical and electronic engineering, a current clamp, also known as current probe, is an electrical device with jaws which open to allow clamping around an electrical conductor. This tool will enable you to find the optimum location for the transducers. Our ultrasonic flow meters are not just for water and waterglycol mixtures. The fluke 373 clamp meter the meter measures truerms ac and dc voltage, ac current. Electromagnetic water flow meter can be mounted in two ways. When servicing the meter, use only specified replacement parts. As shown in a figure at left, a hall element is placed across a gap created by cutting off part of the transformer jaws. An ac clamp meter basically consists of a current transformer in its jaws, bar ct usually. This familyowned business started out making variable flow switches for the automotive industry and today services concrete, defense, chemical processing, mining, wastewater, energy, electronics, laboratories, medical, and many other industries. We offer a wide range of portable and permanent clamp on flow meters.
Having a hinged jaw integrated into an electrical meter allows technicians to clamp the. General constriction of the flow meter is shown in the fig. The new fluke 434, 435 and 437 series ii models help locate, predict, prevent, and. An obstruction orifice is placed in a pipe filled with fluid. Oscilloscope working principle oscilloscope parts and function. This type of measurement is nonintrusive and very convenient.
Rishabh clamp meters are used for measuring, calculating and displaying some of the most vital parameters of single phase or three phase power system. A clamp meter is an electrical test tool that combines a basic digital. Display of the flow meter can be of two types, one is led type and another one is of lcd type. The meter uses large scale of integrated circuit with double integrated ad converter as its core and has full range overload protection the meter can. Pdf traceable technique to calibrate clamp meters in ac.
In general hall elements are used as a sensor to detect dc current because it is not possible to employ an electromagnetic induction method as used for dedicated ac clamp meters. Clamp meter tong tester is one of the most useful test equipment. An overview of clamp meter electrical engineering portal. General clampon meters are specified to achieve two to three per cent uncertainty. Only one conductor is normally passed through the probe. Taking the resistance clamp meter as the object, from signal generation, sensing, detection, filtering, and other aspects the design principle and circuit model is described, the actual data.
Clamp meter in electrical and electronic engineering, a current clamp or current probe is an electrical device having two jaws which open to allow clamping around an electrical conductor. The almageg is an inline electromagnetic energy flowmeter ideal for conductive liquids. The instructions in these warnings must be followed. The ttfm100b series includes a range of ultrasonic flowmeters whose electronics is composed of a single board. Though the clamp is designed solely for current measurement, most clamp meters accept input from test leads or other probes which greatly increases the types of measurements of which they are capable and making the clamp meter a much more versatile instrument. Fundamental principles of clampon ultrasonic flow meters overview of selection, installation, operation and maintenance of clampon meters. Birotor positive displacement meter smartmeasurement. Thereafter connect the electrical appliance to a power source.
An electrical meter with integral ac current clamp is known as a clamp meter, clampon ammeter, tong tester, or colloquially as an amp clamp. This offers the end user the maximum flexibility to choose the technology that best fits his needs. The ufm is a fixed installation, clamp on flowmeter that is easy to install and requires minimum information to be entered by the user. Rishabh clamp meters futuristic clamp meters that stand the test of time. Together, they form a magnetic core during measurements. Aware of the importance of the device to electricians and working professionals, moglix presents a new range of.
This allows properties of the electric current in the conductor to be. A wide variety of sizes are available to accommodate nominal pipe diameters ranging from. The long battery life of these clamp meters make them ideal for usage over a considerable period of time. Both the electronics and guide rail housings form an integral unit that is attached to the pipe using the supplied jubilee clips. The ufm is a fixed installation, clampon flowmeter that is easy to install and requires minimum information to be entered by the user. Utilizing the principle of current transformer, the reading will be displayed. An electric meter or energy meter is an essential device that goes with consumption of commercially distributed energy. When measuring a 3phase circuit, the clamp meter should be applied around the r, s, and t wires all three wires at once. Ttfm100b series toshniwal flow meter, vacuum pumps. Use with caution when working above 30v ac rms, 42v peak, or 60v dc. Fundamental principles of clamp on ultrasonic flow meters overview of selection, installation, operation and maintenance of clamp on meters. Fundamental principles of clampon ultrasonic flow meters.
A clamp meter measures the vector sum of the currents flowing in all the conductors passing through the probe, which depends on the phase relationship of the currents. Clamp meters working principle clamp meters using current transformer for ac measurement current transformer clamp meters are equipped with rigid jaws of made of ferrite iron. One need to set the dial selector on the clamp meter to the correct function and range, which is similar to a normal multimeter. Principles and testing methods of earth ground resistance. With the range switch of the clampon current probe set to 6 amps, the meter indicates 5. Clamp meter amprobe dlc100 the working principle of the clamp meter is identical with that of the ring current transformer which is laced on a current rail, where the rail plays the role of the primary winding with one number of turns. Full overload protection, low battery indication and overrange indication are provided. In the service entrance, clamp around busbars, up to 2. A clamp meter is an electrical test tool that combines a basic digital multimeter with a current sensor. Hold button holds the display reading and symbol is shown in the lcd display, press.
Before use, verify the meters operation by measuring a known voltage. When the hall device drive current id is held constant, the magnetic field b is directly proportional. Description of the meter this meter is a handheld 3 12 digital clamp meter for measuring dc and ac voltage, ac current, resistance, continuity test and insulation test. The jaws are individually wrapped by coils of copper wire. View and download fluke 374 calibration manual online. Their basic operation is like that of a transformer. Leakage current can also be measured by applying the clamp meter around a grounding wire. Taking the resistance clamp meter as the object, from signal generation, sensing, detection, filtering, and other aspects the design principle and. An electrical meter with integral ac current clamp is known as a clamp meter, clamp on ammeter, tong tester, or colloquially as an amp clamp.
Oct 14, 2016 how to install clampon ultrasonic flow meters faqs. It is divided into the current clamp meter, voltage clamp meter and resistance clamp meter according to its function. You must be careful when working with voltages above 30v ac. Sensors a and b work alternately to send and receive ultrasonic pulses. Cm240 digital clamp meter is a 1 3 2 digit lcd multimeter with steady operations, fashionable structure and highly reliable measuring instrument.
Handle electrical applications flawlessly using clamp meters. Ttfm100b series toshniwal flow meter, vacuum pumps and. The ultrasonic flow meter specifically designed for water treatment and chemical industry. In order to successfully test grounding with a c lamp on ground resistance tester, such as aemcs model 6417, the grounding points you are testing require a connection to the utility neutral or other grounding system. The key parts of an oscilloscope that relate to the controls shown in figure 3 are the following.
Birotor positive displacement meter albrpd the smc albrpd flowmeter features two precisely machined rotating members known as helical rotors which rotate and mesh within the meters interior housing in order to form a measuring chamber of known volume which may be used to accurately determine volumetric flow rate as a funtion of the rotors. In general hall elements are used as a sensor to detect dc current because it is not possible to employ an. Having a hinged jaw integrated into an electrical meter allows technicians to clamp the jaws around a wire, cable or other conductor at any point in. Poor grounding contributes to downtime but a lack of good grounding is also dangerous and increases the risk of equipment failure. A dc clampmeter works on the principle of the hall effect. The digital clamp meter is squeezed open, and the cable whose current needs measurement is enclosed in the clamp meter loop. How to install clampon ultrasonic flow meters faqs. Now, push the trigger to open the jaw and clamp it around the wire and close it. In contrast to a multimeter, the clamp meter does not need to be connected to the circuit in order to read current. At this point it will give the user a graphical indication of signal strength, signal quality and a recommended sensor spacing. The pressure of the fluid is measured at two different points.
Assuming a current flowing through a conductor to be the primary. The hall effect, named after edwin hall who discovered it 1879, states that when a conductor carrying current is placed in a magnetic field, a potential is induced across the conductor. Examine the test leads for damaged insulation or exposed metal. Kobold model kdv variable area flowmeter user instructions. Before taking a measurement, the ultrasonic flow meter will guide you to the audible sensor positioning assistant. The cathoderay tube crt, which consists of a screen where signals are viewed, and the elements within the crt, which generate and control a stream of electrons that strike the back inside of the crt screen, producing the illumination you view. Oscilloscope working principle oscilloscope parts and. The clamp meter is an electrical device with jaws open to allow the electrical conductor to be clamped around it. Also how does the working of clamp meter compare to that a current transformer any knowledge would be helpful. Clamp meter display reading is the insulation resistance value. Symbols used on the meter and in this manual are explained in table 1.
If the insulation tester unit is not used, the power switch must shift to power off position, and the test leads must leave the e, l input connect. Clampon ammeter or simply clamp meter is an instrument that is used to measure the current flowing through a conductor. It is a closely held company owned and operated by erik and lars rosaen. This allows measurement of the current in a conductor without the need to. Selection guide to clampon current probes pdf 0702 technical assistance 800 34391. In general ac clamp meters operate on the principle of current transformer ct used to pick up magnetic flux generated as a result of current flowing through a conductor. The clamp meter differs from such current transformers in the construction of the iron core. Over time, corrosive soils with high moisture and salt content and high temperatures can degrade ground rods and their connections. This post will discuss tong tester types, operating principle and how to operate it.
In this article, design idea and design method of a resistance clamp meter are given. Katronic have been working with clampon ultrasonic flow meters for twenty years. A clamp meter is a tool for measuring current on a wire. As a result, there is no down time while units are installed. Electromagnetic flow meter a different parts of the flow meter b assemble view. Digital clamp meter digital clamp meter if the casing is not covered properly, screws are not tightened, do not put it to use. What is the working principle of orifice meter answers. Time difference principle signals are send in and against the flow direction signal with the flow are faster than signals against the flow transit time difference. Sitrans f flowmeters sitrans f us system info and selection guide ultrasonic flowmeters 4152 siemens fi 01 2007 4 overview siemens offers two types of ultrasonic flowmeters, wetted flowmeters and clampon flowmeters.
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