Welcome to MK Test's resource library, where you'll find a range of helpful materials to support your work with our testing solutions.
From user manuals and technical guides to case studies and FAQs, this collection is here to help you make the most of your testing processes. Whether you're troubleshooting or looking to learn something new, we hope you'll find what you need to get the job done efficiently.
Browse resources by type
Automeg FAQs
With high voltage testing (Insulation resistance and HiPot / dielectric testing), it is rarely the test system that defines the testing time. OEMs and specific industries tend to have their own test requirement specification that define:
- Ramp up time (time to charge the wire/harness/net from 0V to test voltage)
- Measurement Dwell (the time during which the high voltage is maintained and the system measures leakage current or insulation resistance)
Here’s an example – a harness with 10 nets needs testing at 1000Vdc. The test specification defines the ramp time as 0.5s (so 1s to ramp to 1000V), and the measurement dwell at 1s. The test time will therefore be at least 100(nets) x [1s (Ramp) + 1s (Measurement)] = 200 seconds. That time is defined purely by the test specification, not the test system.
When you require low voltage testing as well as HV, the low voltage test is nearly negligible compared to the high voltage segment. So, when planning for test time on a harness, the test specification for high voltage test should be your reference document.
If you would like further assistance in calculating accurate test timings, please get in touch. Just send us your test specification and harness/product details, and an application specialist can help.
- Prepare the logo. The logo image needs to be scaled to a suitable size – we recommend 180px wide by 110px high.
- Save the logo in jpeg image format; it must be named CustomerLogo.jpg
- Copy the logo to the following location on the PC hosting MKAT Runner: C:ProgramDataMK Test Systems LimitedReportsLogos. Note: You’ll need to replace the existing file of the same name in this folder.
- That’s it! From now on, all default reports will display your company logo in the top right position as shown below.
Yes, Automeg does have a simple self-test routine. We recommend performing system self-tests at regular intervals to ensure optimal performance of all critical components like switching relays, power supplies, measurement and stimulus circuits, etc.
The frequency of performing self-test depends on several factors such as how often the system is used and how many test points are in your system, among others. It is very common for users to perform self-test at regular intervals such as when the system is turned-on, at the beginning of each shift or prior to executing every job.
You can also set Automeg to run self-test automatically every time the system is switched on.
We have a full blog article answering this question here.
We have a full blog article answering this question here.
We have a full blog article answering this question here.
RTS FAQs
Yes, the RTS system is scalable and will automatically detect new nSat and uSat devices when added. This means that the system can be expanded at a later date by adding more MAG connectors and umbilical sections to accommodate more nSat or uSat devices.
At this time, Umbilical sections are available in lengths of 0.5m, 1m, 3m, 5m, 10m, 15m, 20m, 30m & 50m. The total length of a single umbilical must not exceed 100m.
The total number of nSat or uSat devices on one umbilical must not exceed 48.
The Umbilical Connection Module (UCM) allows up to 4 umbilicals connected at each time.
The uSat has a higher number of test points available than the nSat and can be easily thought of as 2, 4 or 6 nSats in one box!
If you have a high density of connectors and test points in one location a uSat can be used giving you up to 360 test points to connect everything up at once and only one Umbilical connection (MAG connector) required.
Speak to us about custom formats using the uSat hardware with even higher test point densities such as ARINC 404/600 housings for aerospace applications.
Absolutely! All MK Test System products use the MKAT Gen3 Software suite and this includes the RTS system. This means that you will already be familiar with all the common functions. Importing and running test programs, viewing results and using advanced features such as Manual Mode and Probe Mode within the MKAT Runner application are all the same as MKAT for Automeg. Creation of test programs and management of the system is also still done using the MKAT Editor and you can even use the powerful functions of the Automatic Program Generator (APG) tool to generate RTS programs.
To make the most of the advanced features of RTS, a new RTS sub-test is available. This is a new display screen allowing the user to view and sort results in real time whilst the scanning is in progress.
Along with this, some new features for interface harness management and hardware configuration have been introduced to the MKAT Runner to make the operator’s life easier.
ExLRT FAQs
Although both products use the same MK52 couplers, it is not possible to use a BLRT loop or joint cable on an ExLRT or vice versa. Although the cables look the same, the connectors are different which means they can only be used for the specific product they’re designed for.
Clamps are mechanical items which use a physical pressure to pass electrical signal into the UUT (like two wires soldered together). Clamps are therefore used for DC bond testing – we use 1A, 10A and 150A bond clamps.
Couplers magnetically transfer an electrical AC signal into the UUT. They’re used for AC non-intrusive testing of loops and joints because they can pass the current across air gaps. We use MK52 couplers for these measurements and tests. The commonly used i400 clamps are actually couplers, which is confusing!
Simply put, ExLRT Record Mode means you no longer have to manually enter data into a laptop, PC or paper task card when taking measurements.
Operators can measure, review and save data directly in the tool, then update to a PC. For more information, you can download the guide here or read this blog article.
You can send the cable and couplers back to us for repair. To arrange this, please submit a support ticket on the service page and one of our team will be in touch.
Identifying the right tool for aircraft OEM (Original Equipment Manufacturer) bond and loop testing requirements can be complex.
As an MRO, your first point of call should be the AMM (maintenance manual). However, some OEMs are more prescriptive than others. And with a broad range of similar tools available on the marketing all claiming to comply with OEM requirements, how do you know for sure which tool is right?
MK’s range of bond testing tools are the BLTU4, BLRT and ExLRT. These are often mentioned alongside the legacy industry tool, the LRT. To help differentiate between all the tools, we’ve explained which one is recommended for each original equipment manufacturer:
Airbus
All loop resistance testing on Airbus aircraft must be carried out at 1KHz, so the BLTU4 is the right tool. Airbus do not require joint testing, only loop and bond. We can support with proving equivalency to Airbus for using the BLTU4 within your operation – get in touch with us for details.
Boeing
All loop resistance testing on Boeing aircraft must be carried out using 200Hz. In addition to loop resistance testing, Boeing also demand specific joint tests, variance tests and stray current tests – the BLRT is the recommended tool for this.
Both the BLRT and ExLRT are approved for use by Boeing. What’s the difference between the two? The ExLRT is certified as Intrinsically Safe and is therefore the best tool for MROs working on fueled aircraft. However, the BLRT is the tool which has full bond, loop and joint capabilities.
Depending on your requirements and working environment, either of these tools may be suitable for you. They’re both lighter and smaller than the legacy LRT, and can be operated by a single person.
To learn more about the differences between BLRT and the ExLRT, read this article.
Bombardier
Bombardier are aligned with the Airbus specification of 1000Hz, so we therefore recommend the BLTU4.
COMAC
COMAC have specified the use of the BLTU4 tool in the AMM for ARJ21 aircraft models.
Embraer
Embraer follow Boeing in terms of frequency and types of test required, so the BLRT or ExLRT would be the most suitable tools.
Summary
Visit the dedicated product pages for BLRT, BLTU4 and ExLRT to learn more about each of our bond and loop testing tools. To learn more about the differences between our tools and the legacy Boeing-approved LRT, visit our blog and filter by ExLRT.
We have a detailed blog article answering this question here.
We have a detailed blog article answering this question here.
MKAT Software FAQs
MKAT Editor software does not require a login. For the Runner software, systems are set up with 3 default logins. The user names are not case sensitive but the passwords are:
- User name: Administrator. Password: MKtest2016
- User name: Advanced Programmer. Password: MKtest2013
- User name: Operator. Password: Mktest21013
No, MK Test Systems developed MKAT to make testing simpler, automated and to save the user time and money. MKAT is supplied with a user guide.
We also offer monthly training webinars which are free of charge. Details and dates of these are on the training page. If dedicated onsite training is required, just ask your MK Sales Manager or complete an enquiry form on the training page.
We have a full blog article answering this question here.
We no longer support our gen2 software so recommend that all customers upgrade to gen3 MKAT. For more FAQs about this topic, read our dedicated article here.
- Prepare the logo. The logo image will need to be scaled to a suitable size – we recommend 180px wide by 110px high.
- Save the logo in jpeg image format; it must be named CustomerLogo.jpg
- Copy the logo to the following location on the PC hosting MKAT Runner: C:ProgramDataMK Test Systems LimitedReportsLogos. Note: You’ll need to replace the existing file of the same name in this folder.
- That’s it! From now on, all default reports generated by MKAT Runner will display your company logo in the top right position as per the example shown below.
We occasionally have customers contacting us for help when they’re creating an MKAT test program. The conversation is usually along the lines of “I’ve run the APG in the MKAT Editor but it didn’t create a program. Where did I go wrong?”.
This fairly common query can be resolved with just a few changes – we’ve written a dedicated article here.
- In the Runner, go to Configuration and select the Parameters tab
- Select the desired report from the Default Report menu
- Apply the change
From now on, this report will be automatically selected to display the test results.
We have a detailed blog article answering this question here.
For example, with a harness that goes into a junction box and splits off into multiple different looms, can I just map the connections at each end in the netlist and map the test point connections at either end of the harness in the Xref?
The ability to resolve internal connections is only there for the occasions where you have not already mapped the end to end connections. So, if you have an internal component such as a terminal block and you have already worked out the route through the component, then yes you simply enter the extremity From-To details in the netlist and XRef and the system will test from the one extremity to the other.
One tip is to put the terminal block reference (or other component) in the “connection detail” field in the netlist, so when the report shows a failure between the two extremities you will see on the report that the circuit passes through a terminal block and you will know to go look there for the fault.
Driven by our goal of simplifying an automatic test sequence for the end user, the new generation of software keeps your testing process as simple as possible.
Operator instructions and prompts can easily be added to any program, with automatic test reports, export to quality systems without manual intervention and fault diagnosis tools assisting the operator in informing of the nature of the fault and what to do next. This leads to easier, time saving and traceable test programs. More details can be found on the MKAT page.
MK Test Systems stopped supporting Gen2 after 31 Dec 2020. This included updates, amendments revisions or improvements for Gen2 software.
A lot of features have been included in MKAT, and more are on the roadmap to be added in future versions. Details of upcoming new features are on the MKAT page and also on our Tech::Lab page, which is dedicated to sharing our NPD news.
A very few limited number of features will not be in MKAT Gen3. To check if a feature you use is included, please ask your MK Test Systems Sales Manager, or email sales@mktest.com.
MKAT is compatible with Windows 10 and 11. The minimum PC spec is:
- Processor: i5
- RAM: 16Gb minimum
- HHD: 160 GB minimum
- Operating system: Windows 10/11 (64 bit)
MKAT includes a Gen2 to Gen3 translator and generally, Gen2 test programs will translate in less than a minute. Get in touch with details of your current Gen2 release revision and we will advise if there are likely to be any issues.
MKAT also includes a powerful APG (Automatic Program Generation) toolset that allows you to create programs from imported source net/circuit data in seconds. More complex programs may need some manual re-configuration to enable you to take full advantage of MKAT.
The Program Version displays on our standard reports by design, so it can’t be removed directly. However, there are two options for achieving a more customised look:
- Custom report option: For customers who need full control over what appears on their reports, we offer custom report setups. With a custom report, you can specify exactly what you want displayed. While this option does involve additional time and costs, it’s suitable for customers who need a tailored reporting solution. Just keep in mind that because custom reports require specific updates whenever we release new software, future updates may need a bit of extra planning.
- Request a software change: An alternative is to request a software change that would allow the program version to be hidden across all standard reports. This route benefits everyone, as it makes the option available to all customers with minimal maintenance during software updates.
Both options provide flexibility, and we’re here to help make sure your reporting needs are met. For either option, please raise a support ticket to get started.
BLRT and BLTU FAQs
Once the system is powered on, click the MK software logo to get started.
The login screen will then be displayed – enter the following login details:
- User: operator
- Password: Mktest21013
We recommend that a backup is done first using “MKAT Data Tools”:
- Exit the software
- Run MKAT Data Tools
- Back up all data / config
- Uninstall the software
- Install the new version
Identifying the right tool for aircraft OEM (Original Equipment Manufacturer) bond and loop testing requirements can be complex.
As an MRO, your first point of call should be the AMM (maintenance manual). However, some OEMs are more prescriptive than others. And with a broad range of similar tools available on the marketing all claiming to comply with OEM requirements, how do you know for sure which tool is right?
MK’s range of bond testing tools are the BLTU4, BLRT and ExLRT. These are often mentioned alongside the legacy industry tool, the LRT. To help differentiate between all the tools, we’ve explained which one is recommended for each original equipment manufacturer:
Airbus
All loop resistance testing on Airbus aircraft must be carried out at 1KHz, so the BLTU4 is the right tool. Airbus do not require joint testing, only loop and bond. We can support with proving equivalency to Airbus for using the BLTU4 within your operation – get in touch with us for details.
Boeing
All loop resistance testing on Boeing aircraft must be carried out using 200Hz. In addition to loop resistance testing, Boeing also demand specific joint tests, variance tests and stray current tests – the BLRT is the recommended tool for this.
Both the BLRT and ExLRT are approved for use by Boeing. What’s the difference between the two? The ExLRT is certified as Intrinsically Safe and is therefore the best tool for MROs working on fueled aircraft. However, the BLRT is the tool which has full bond, loop and joint capabilities.
Depending on your requirements and working environment, either of these tools may be suitable for you. They’re both lighter and smaller than the legacy LRT, and can be operated by a single person.
To learn more about the differences between BLRT and the ExLRT, read this article.
Bombardier
Bombardier are aligned with the Airbus specification of 1000Hz, so we therefore recommend the BLTU4.
COMAC
COMAC have specified the use of the BLTU4 tool in the AMM for ARJ21 aircraft models.
Embraer
Embraer follow Boeing in terms of frequency and types of test required, so the BLRT or ExLRT would be the most suitable tools.
Summary
Visit the dedicated product pages for BLRT, BLTU4 and ExLRT to learn more about each of our bond and loop testing tools. To learn more about the differences between our tools and the legacy Boeing-approved LRT, visit our blog and filter by ExLRT.
We have a detailed blog article answering this question here.
Portable Automeg FAQs
Portable Automeg is about the size of a small suitcase. The system is housed in a protective Peli case which has an extended handle and wheels and an IP66 rating.
External dimensions are around 600 x 400 x 260mm, depending on the final system specification.
The Peli case is ruggedised, with anti-vibration mounts fitted.
Yes it can.
The Portable Automeg was originally designed for - and continues to be used in - submarines, where space is at an absolute premium. A removable lid is optional but vital in certain applications.
Yes! We've designed the Portable to as closely replicate the capability of the standard Automeg systems, and this includes the software and therefore creation and running of test programs.
Go to the MKAT software page to learn more.
Typically yes, but we can also offer a battery version.
Yes. A ticket printer option is available.
The Portable Automeg can have up to 512 test points (256 test points maximum for 4 wire measurements).
Yes. We offer the Portable Automeg as an 'E' model which is capable of performing excitation measurements. There is an option to include a fixed internal power supply to enable functional testing on the unit under test (UUT).
AC (Alternating Current): An electric current in which the flow of charge reverses direction many times a second at regular intervals.
Accuracy: The accuracy of a digital tester is defined as the difference between the reading and the true value for a quantity measured in reference conditions.
Active Power: A term used for power when it is necessary to distinguish among Apparent Power, Complex Power and its components, and Active and Reactive Power.
Actuator: In electrical engineering, the term actuator refers to a mechanism that causes a device to be turned on or off, adjusted or moved, usually in response to an electrical signal. An example is a motor that closes blinds in response to a signal from a sunlight detector. Actuators enable computers to control complex manufacturing processes without human intervention or supervision.
AMM: This is an acronym used by The Boeing Company; it stands for Aircraft Maintenance Manual.
Ammeter: An instrument for measuring the flow of electrical current in amperes.
Ampacity: The maximum amount of electrical current that a device or conductor can carry before sustaining deterioration.
Amperage (Amps/Amperes/Ampacity/Rated Amperage): The standard unit of electrical current; the measurement of the flow rate of electricity. A water hose analogy is helpful here – in terms of water through a hose, amperage would be a measure of the volume of water flowing through the hose.
Ampere-Hour (Ah): A unit of measure for battery capacity; the use of one ampere for one hour. It is obtained by multiplying the current (in amperes) by the time (in hours) during which current flows. For example, a battery which provides 5 amperes for 10 hours is said to deliver 50 ampere-hours.
Apparent Power (measured in volt-amps): The product of the applied voltage and current in an ac circuit.
Arc flash: An arc flash is caused by current flowing between two conducting surfaces and most commonly occurs as a result of faulty equipment or poor work practices. Left unchecked, arc flashes release a huge amount of energy in a high-pressure blast, which can result in serious injuries and damage.
ATE: automatic test equipment
ATEX: An abbreviation for “ATmosphere EXplosible”. ATEX is also the abbreviated name of the European Directive 2014/34/EC concerning the placing on the market of explosion-proof electrical and mechanical equipment, components and protective systems. It came into force on 1 July 2003, and all new equipment and protective systems have been subject to it since that date.
Back-to-back connection: In HVDC terms, links used to connect neighboring grids are often referred to as “back-to-back” connections, indicating that the distance between the two grids is minimal. Such connections are able to link independent power grids, including those operating at different frequencies, and enable power to flow from one grid to another. This means that generators on either grid can be used to secure the supply of electricity across the extended network. The connections can also improve voltage and frequency stability in the linked grids. Note: The term “back-to-back connection” is also used to describe a test set-up for electrical devices where a motor and a generator are connected to the same shaft line.
Balanced cable / balanced line: A cable having two identical conductors that carry voltages of opposite polarities and equal magnitude with respect to ground. The conductors are twisted to maintain balance over a distance.
Balanced transmission: A mode of signal transmission in which each conductor carries the signal of equal magnitude, but opposite polarity. A 5 volt signal for example, appears as a +2.5 Volts on one conductor and -2.5 Volts on the other.
Balun: An impedance matching transformer that converts the impedance of one interface to the impedance of another interface. Generally used to connect balanced twisted pair cabling with unbalanced coaxial cabling. The term is derived from “balanced / unbalanced”.
Bandwidth: Bandwidth in electronic communication is the difference between the highest- and the lowest-frequency signal in a given transmission medium. It is measured in hertz (Hz).
BLRT: Bond, Loop and Joint Tester – we recommend the MK Test Systems version! See also BLTU, ExLRT and Bonding.
BLTU: Bond and Loop Tester – as above, we recommend the MK Test Systems version! See also BLRT, ExLRT and Bonding.
Bonding: A method used to produce good electrical contact between metallic parts. Also refers to the grounding bars and straps used in buildings to bond equipment to an approved ground.
BPS: Bits per second.
Braid: Fine wires interwoven to form a tubular flexible structure that may be applied over one or more wires for the purpose of shielding. May also be formed into a flattened conductor to be used as a grounding strap.
Breakdown: Failure of electrical insulation to provide a dielectric barrier to the flow of current.
Breakdown voltage: The voltage at which the electrical insulation between two conductors fails.
Cable: A cable is a set of wires, usually encased in an outer protective jacket. A “cord” would be a cable by this definition so far, but a cable is part of a permanent installation; a cord is more flexible and often has a plug end for a portable appliance or lamp.
Cable Harness: A string of cables and/or wires which transmit informational signals or operating currents (energy). The cables are bound together by clamps, cable ties, cable lacing, sleeves, electrical tape, conduit, a weave of extruded string, or a combination thereof.
Calibration: Adjustment of a device so the output is within a specified range for particular values of the input.
Capacitance: The ability of a device to store an electrical charge.
Capacitor: A multipurpose device that can store electrical charge in the form of an electric field. Capacitors are used to buffer electricity (smooth out peaks) and to guard against momentary voltage losses in circuits (when changing batteries, for example).
Capacitor bank: Several capacitors connected in parallel.
Cathode: The negative electrode that emits electrons or gives off negative ions and toward which positive ions move or collect in a voltaic cell or other such device. Also the term for the negative pole of a battery.
CE: An EU standard of safety, the CE marking on end products indicates compliance with all applicable directives. CE stands for Conformite Europeene.
Circuit: A closed path in which electrons from a voltage or current source flow. Circuits can be in series, parallel, or in any combination of the two.
Circuit breaker: Devices that interrupt high currents to protect electrical equipment from damage caused by current surges, eg, from a short circuit or a
lightning strike. To restore service, the circuit breaker must be reset (closed) after correcting the cause of the overload or failure. Circuit breakers are used in conjunction with protective relays to protect circuits from faults.
Clamp: See coupler.
Conductivity: The capability of a conductor to carry electricity, usually expressed as a percent of the conductivity of a same sized conductor of soft copper.
Conductor: An electrical conductor is any substance through which electrical current can flow. Since electrical current is a process involving the flow of electrons, how well a material conducts electricity depends on its atomic structure and chemical consistency. Copper and aluminium are the most common materials used for electrical wiring, whereas silver is the best conductor but is expensive. Gold is sometimes used for high-quality surface-to-surface contacts. Semi-conductors are materials whose ability to conduct electricity can be controlled. Super-conductors, under special conditions, offer no electrical resistance, so electricity can flow indefinitely.
Connector: A female cord mounted wiring device with the conducting elements recessed behind the mating surface. This type of device is normally wired to be live when nothing is plugged in to it. Therefore, connectors are wired to the source of power.
Converter: An electrical device, comprising a rectifier and inverter, used to alter the voltage and frequency of incoming alternating current in an electrical system. The term may also refer to inverters, rectifiers or frequency converters. (See also Converter station, Inverter, Rectifier, Frequency converter).
Converter station: Special equipment is needed to convert electricity from alternating current (AC) to direct current (DC), or vice versa. High-voltage DC (HVDC) converter stations use power electronic devices called thyristors to make these conversions. (See also HVDC and HVDC Light.)
Coupler: A device for transferring electrical energy from one circuit to another. Also known as a clamp.
Coupling transformer: A coupling transformer is a device that permits two (usually) separate circuits to influence one another. Such a setup can be desirable for control purposes. It can also be used, for example, to inject high frequency signals into power lines for communications purposes.
Creepage distance: The shortest distance between two conductors as measured along the device that separates them. Creepage Distance is normally a design parameter of insulators or insulating bushings.
Current: The rate of flow of electrical energy through a conductor or wire, comparable to the amount of water flowing in a pipe. Electric current is measured in amperes or “amps”.
Cycle: The change in an alternating electrical sine wave from zero to a positive peak to zero to a negative peak and back to zero.
dBm: Decibels compared to one milliwatt. The higher the dBm, the higher the devices transmit or receive power.
DC: See Direct Current.
Decibel (dB): A unit used to express the magnitude of change in level of electric signal or sound intensity. A voltage ratio of 1 to 10 is equal to -20dB, 10 to 1 to 20dB, 100 to 1 to 40dB and 1000 to 1 to 60dB. A power ratio of 10 to 1 is not 20dB, but 10dB, since power(P) is proportional to the square of voltage(V).
Defence/Defense: One of MK Test Systems’ key industries. Learn more here.
Demand: The average value of power or related quantity over a specified period of time.
Dielectric: 1) Any electrical insulating medium between two conductors. 2) The medium used to provide electrical isolation or separation.
Dielectric constant: A number that describes the dielectric strength of a material relative to a vacuum, which has a dielectric constant of one.
Dielectric strength: The maximum electric field that a pure material can withstand under ideal conditions without breaking down (i.e., without experiencing failure of its insulating properties).
Dielectric test: A test that is used to verify an insulation system. The tests involve the application of a voltage higher than that of the rated voltage for a specified time for the purpose of determining the adequacy against breakdown of insulating materials and spacing under normal conditions.
Dielectric withstand: The ability of insulating materials and spacings to withstand specified overvoltages for a specified time (one minute unless otherwise stated) without flashover or puncture.
Diode: A semiconductor device with two terminals, typically allowing the flow of current in one direction only. The function of a diode is to allow current in one direction and to block current in the opposite direction. The terminals of a diode are called the anode and cathode.
Direct Current (DC): Current which moves in a single direction in a steady flow. Normal household electricity is alternating current (AC) which repeatedly reverses its direction. However, many electronics devices require DC, and therefore must convert the current into DC before using it.
Electrolyte: Any substance (as an acid or salt) that when dissolved (as in water) conducts an electric current. As an example, the sulfuric acid-water solution in a storage battery is an electrolyte.
Electromotive Force (EMF): A difference in potential that tends to give rise to an electric current. Measured in volts.
Electron: A tiny particle which rotates around the nucleus of an atom. It has a negative charge of electricity.
Electron Theory: The theory which explains the nature of electricity and the exchange of “free” electrons between atoms of a conductor. It is also used as one theory to explain direction of current flow in a circuit.
Farad: A unit of measure for capacitance. One farad is equal to one coulomb per volt.
Ferrite: A ferrimagnetic ceramic non-conductive compound material used to prevent high frequency electrical noise from entering or exiting the equipment.
Ferroresonance: A type of resonance in electric circuits which occurs when a circuit containing a nonlinear inductance is fed from a source that has series capacitance, and the circuit is subjected to a disturbance such as opening of a switch. It can cause overvoltages and overcurrents in an electrical power system and can pose a risk to transmission and distribution equipment, as well as to operational personnel. Also known as nonlinear resonance.
Frequency: The number of complete cycles of a wave-form per second, measured in Hertz (Hz). If a current completes one cycle per second, then the frequency is 1 Hz; 60 cycles per second equals 60 Hz.
Fuse: A safety device consisting of a strip of wire designed to melt and break an electric circuit if the current exceeds a safe level. To restore service, the fuse must be replaced using a similar fuse with the same size and rating after correcting the cause of failure.
Generator: A device that converts one form of energy into another, especially mechanical energy into electrical energy.
Ground: The reference point in an electrical circuit from which voltages are measured, a common return path for electric current, or a direct physical connection to the Earth.
Ground-Fault Circuit-Interrupter (GFCI): An electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor. Such an imbalance is sometimes caused by current leakage through the body of a person who is grounded and accidentally touching the energized part of the circuit.
Henry (H): A unit of measure for inductance. If the rate of change of current in a circuit is one ampere per second and the resulting electromotive force is one volt, then the inductance of the circuit is one henry.
Hertz (Hz): A unit of measure for frequency, equal to one cycle per second. Hertz replaces the earlier term of cycle per second (cps). Most international devices are typically 50 hertz, whereas U.S. devices are typically 60 Hertz. In alternating current, a hertz is the number of changes of the negative and positive poles per second.
IEC (International Electrotechnical Commission): The international organization that prepares and publishes standards for all electrical, electronic and related technologies.
Impedance: The measure of the opposition that a circuit presents to a current when a voltage is applied. Impedance extends the concept of resistance to AC circuits, and possesses both magnitude and phase, unlike resistance, which has only magnitude.
Inductance: The property of a conductor by which a change in current flowing through it creates an electromotive force in both the conductor itself (self-inductance) and in any nearby conductors (mutual inductance). Measured in henry (H).
Inductor: A coil of wire wrapped around an iron core. The inductance is directly proportional to the number of turns in the coil.
Inrush Current: The initial surge of current experienced before the load resistance of impedance increases to its normal operating value.
Insulation: A non-conductive material used on a conductor to separate conducting materials in a circuit.
Insulator: Any material where electric current does not flow freely. Insulative materials, such as glass, rubber, air, and many plastics have a relatively high resistance. Insulators protect equipment and life from electric shock.
Inverter: An apparatus that converts direct current into alternating current.
IP (Ingress Protection) Rating: A two digit code, and an optional letter, specifying the level of protection from foreign objects with the first digit referring to protection from solids and the second digit referring to protection from liquids. The optional letter can be appended to classify only the level of protection against access to hazardous parts by persons or to provide additional information related to the protection of the device.
Jacket: The outer material layer of a cable.
Jitter: The slight movement of a transmission signal in time or phase that can introduce errors and loss of synchronization. More jitter will be encountered with longer cables, cables with higher attenuation, and signals at higher data rates.
Joule (J): A measurement of energy or work. In mechanical systems, it’s the force of one newton, moving an object a distance of one meter. In electronics, it’s the same amount of energy, in electrical units. One joule is one watt of power, applied for one second (a watt-second); or a coulomb of electrical charge raised to a potential of one volt.
Kabelsalat: Ok, so this one isn’t a technical term, but we like it! Kabelsalat is the German word for a tangled mass of wires. Literally, ‘cable salad’. See also “snake’s wedding”.
Kilovolt Ampère (kVA): Apparent power expressed in Thousand Volt-Amps. kVA rating designates the output which a transformer can deliver at rated voltage and frequency without exceeding a specified temperature rise.
Kilovolt Ampère Reactive (kVAR): The measure of additional reactive current flow which occurs when the voltage and current flow are not perfectly synchronized or not in phase.
Kilowatt (kW): Actual power expressed in Kilowatts. Equal to 1000 watts.
Kilowatt-hour (kWh): The product of power in kW and time in hours. Equal to 1000 Watt-hours. For example, if a 100W light bulb is used for 4 hours, 0.4kWhs of energy will be used (100W x 1kW / 1000 Watts x 4 hours). Electrical energy is sold in units of kWh.
L: A symbol used to express inductance. The unit of measure is a “Henry”.
LED: Light Emitting Diode. A semiconductor diode that emits light when conducting current and is used in electronic displays, indoor and outdoor lighting, etc.
Load: Anything which consumes electrical energy, such as lights, transformers, heaters and electric motors.
Load Rejection: The condition in which there is a sudden load loss in the system which causes the generating equipment to be over-frequency. A load rejection test confirms that the system can withstand a sudden loss of load and return to normal operating conditions using its governor. Load banks are normally used for these tests as part of the commissioning process for electrical power systems.
LRT: A Loop Resistance Tester is a portable electronic instrument for measuring the resistance of electronic cable shielding as installed in aircraft, without requiring the cables to be disconnected. It comprises three elements: couplers, joint probes, and an instrument assembly. The couplers are used to measure the loop resistance formed by the shielding in the cable under test and airplane structure. The joint probes are used to measure the resistance of joints in the cable (cable-to-backshell, connector-to-bracket) to isolate bad joints if the loop measurement is out of tolerance. Also see BLRT, BLTU and ExLRT.
Megohmmeter: A testing device that applies a DC voltage and measures the resistance (in millions of ohms) offered by the equipment or conductor’s insulation.
MRO: Maintenance, Repair and Overhaul. A vital support function in the aviation industry, MROs offer a wide variety of services essential to ensuring aircraft remain operational, fully functional and safe.
Mutual Induction: Occurs when changing current in one coil induces voltage in a second coil.
Nano satellite (nSat): Miniaturised electrical test switching satellite and one of the component parts in the RTS high speed test system. The nSat brings the test points directly to the UUT, eliminating umbilical cables. Designed for MK Test Systems’ RTS (Real-Time Scanning) harness test system.
OEM: Original Equipment Manufacturer. MK Test Systems provides OEMs with test systems for use on their final assembly lines. We also work with MROs.
Ohm: (Ω) A unit of measure of electrical resistance. One ohm is equivalent to the resistance in a circuit transmitting a current of one ampere when subjected to a potential difference of one volt.
Ohm’s Law: The mathematical equation that explains the relationship between current, voltage, and resistance. Ohm’s Law is used for calculating voltage drop, fault current and other characteristics of an electrical circuit. U=IR; I=U/R; R=U/I; Where U = Voltage impressed on a circuit, I = current flowing in a circuit and R = circuit resistance.
Ohmmeter: An instrument for measuring the resistance in ohms of an electrical circuit.
Open Circuit: An open or open circuit occurs when a circuit is broken, such as by a broken wire or open switch, interrupting the flow of current through the circuit. It is analogous to a closed valve in a water system.
Oscilloscope: A device that allows you to see how voltage changes over time by displaying a waveform of electronic signals.
Parallel Circuit: A circuit in which there are multiple paths for electricity to flow. Each load connected in a separate path receives the full circuit voltage, and the total circuit current is equal to the sum of the individual branch currents.
Peak to Peak: The amplitude of the AC wave form from its positive peak to its negative peak.
PF: Power Factor
Phase Angle: The angular displacement between a current and voltage waveform, measured in degrees or radians.
Phase Rotation: Phase rotation defines the rotation in a Poly-Phase System and is generally stated as “1-2-3”, anti-clockwise rotation.
Pigtail: A very short patch cable or wiring adapter. Primarily used in the automotive industries where a longer cable assembly is not needed.
Pin and Sleeve: Common term in reference to an IEC60309 device outbound link.
Plug: A male cord mounted wiring device with the conducting pins protruding and exposed. This type of device should never be wired to make the exposed pins live while unplugged; they should always be ‘dead’ until they are plugged into a power source such as a wall or generator outlet.
Polarized: A plug and connector formed in a way that only allows proper connection.
Polarity: The electrical term used to denote the voltage relationship to a reference potential (+). A collective term applied to the positive (+) and negative (-) ends of a magnet or electrical mechanism such as a coil or battery.
Power: The rate at which electrical energy is transferred by an electric circuit. Measured in Watts.
Power Factor: The ratio of energy consumed (watts) versus the product of input voltage (volts) times input current (amps). In other words, power factor is the percentage of energy used compared to the energy flowing through the wires. Adding capacitors to the system changes the inductive effect of the ballast coils, converting a Normal Power Factor (NPF) to a High Power Factor (HPF) system.
Protective Relay: A relay device designed to trip a circuit breaker when a fault is detected.
Quality Assurance: In lieu of any genuine electrical terms beginning with the letter Q, we’re using this opportunity to highlight how we can help improve your quality assurance. Using our test systems means your products are delivered to your end customer certified as 100% correctly wired.
Quick: Our test systems are quick! They help speed up testing time in several ways, cumulatively saving up to 30% testing time in the case of RTS, our next-generation wire harness test system.
Range: Nominal operating limits, specified by the lowest calibration point to the highest calibration point.
Reactive power: The portion of electricity that establishes and sustains the electric and magnetic fields of AC equipment. Exists in an AC circuit when the current and voltage are not in phase. Measured in VARS.
Real power: The average value of the instantaneous product of volts and amps over a fixed period of time in an AC circuit.
Rectifier: An electrical device that converts an alternating current into a direct one by allowing a current to flow through it in one direction only.
Reference range: A specific range of values of an influence quantity within which the transducer complies with the requirements concerning intrinsic errors.
Reference value: A specified single value of an influence quantity at which the transducer complies with the requirements concerning intrinsic errors.
Reference conditions: Conditions of use for a transducer prescribed for performance testing, or to ensure valid comparison of results of measurement.
Relay: An electrical coil switch that uses a small current to control a much larger current.
Reluctance: The resistance that a magnetic circuit offers to lines of force in a magnetic field.
Residual current: The algebraic sum, in a multi-phase system, of all the line currents.
Resistance: The opposition to the passage of an electric current. Electrical resistance can be compared to the friction experienced by water when flowing through a pipe. Measured in ohms.
Resistor: A device usually made of wire or carbon which presents a resistance to current flow.
Root-Mean-Square (RMS): The effective value of alternating current or voltage. The RMS value equates an AC current or voltage to a DC current or voltage that provides the same power transfer.
Rotor: The rotating part of an electrical machine such as a generator, motor, or alternator. Used in slip rings, which can be tested using a slip ring tester.
RTS: Real-time scanning. MK’s RTS wire harness test system is modular, and offers high speed testing during harness installation and build.
Self induction: Voltage which occurs in a coil when there is a change of current.
Semiconductor: A solid substance that has a conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects. Devices made of semiconductors, notably silicon, are essential components of most electronic circuits.
Series-parallel circuit: A circuit in which some of the circuit components are connected in series and others are connected in parallel.
Series circuit: A circuit in which there is only one path for electricity to flow.
Short circuit: When one part of an electric circuit comes into contact with another part of the same circuit, diverting the flow of current from its desired path.
Slip ring: An electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. A slip ring can be used in any electromechanical system that requires rotation while transmitting power or signals.
Slip ring tester: Also known as SRT, MK’s specialist test system is a modern upgrade to the legacy slip testers commonly used in the slip ring manufacturing sector.
Solid state circuit: Electronic (integrated) circuits which utilize semiconductor devices such as transistors, diodes and silicon-controlled rectifiers.
Stator: The stator is the stationary part of rotary electromagnetic devices like the alternator, electric motor, or generator.
Terminal: A terminal is the point at which a conductor from an electrical component, device or network comes to an end and provides a point of connection to external circuits. A terminal may simply be the end of a wire or it may be fitted with a connector or fastener. The connection may be temporary, as for portable equipment, or may require a tool for assembly and removal, or may be a permanent electrical joint between two wires or devices.
Transistor: A semiconductor device with three connections, capable of amplification in addition to rectification.
True power: Measured in Watts. The power manifested in tangible form such as electromagnetic radiation, acoustic waves, or mechanical phenomena. In a direct current (DC) circuit, or in an alternating current (AC) circuit whose impedance is a pure resistance, the voltage and current are in phase.
VAR: Volt Ampère Reactive. Also see “Reactive power”.
Variable Resistor: A resistor that can be adjusted to different ranges of value.
Volt (V): A unit measure of voltage. The electrical potential needed to produce one Ampère of current with a resistance of one ohm.
Voltage: An electromotive force or “pressure” that causes electrons to flow and can be compared to water pressure which causes water to flow in a pipe. Measured in volts.
Voltage drop: The loss of voltage in a circuit when current flows.
Volt-Ampere (VA): 1) A unit of measure of electrical power. 2) Volt Ampère rating designates the output which a transformer can deliver at rated voltage and frequency without exceeding a specified temperature rise.
Voltmeter: An instrument for measuring the force in volts of an electrical current. This is the difference of potential (voltage) between different points in an electrical circuit. Voltmeters have a high internal resistance are connected across (parallel to) the points where voltage is to be measured.
Watt: A unit of electrical power, defined as one joule per second. Wattage is calculated as Voltage x Amperage.
Watt-hour (Wh): A unit of electrical energy equivalent to a power consumption of one watt for one hour.
Wattmeter: The wattmeter is an instrument for measuring the electric power (or the supply rate of electrical energy) in watts of any given circuit.
Waveform: A graphical representation of electrical cycles showing the amount of variation in amplitude over a defined period of time.
Wire Harness: An assembly of electrical wires bound together with insulating materials, used in the electrical system of a machine such as an aircraft or computer. Also known as cable harness, a wiring assembly or wiring loom.
X: The symbol used to denote reactance, measured in the unit of ohms (Ω).
Z: The symbol used to denote impedance, measured in the unit of ohms (Ω).
Please contact us via sales@mktest.com to request a product specification.
Our case studies showcase customers from all over the world, in a variety of sectors.
Application notes go into more detail of the system specs and requirements for specific real-life customer applications. Lastly, our industry spotlights are overviews for specific sectors - they frequently include ROI as well as mini case studies.