Contactors & Motor Starters Introduction Literature FAQ Photos Contactors & Motor Starters Question: What is special about the MCI Compressor Starter? Can I use a “normal” MCI soft starter to soft start a compressor?    Answer: Yes, a normal MCI can be used to control (soft start) a compressor. The difference is that the MCI Compressor soft starter is pre-set from factory to ensure fast and reliable start of three phase compressors. Question: Can the MCI soft starter be used as a switch or do I need also to install a contactor?    Answer: The MCI can be used as a switch, therefore it is not necessary to use an additional contactor. The type of equipment that can be used for operational switching is specified in EN 60364-5. Included here are: contactors and semiconductor devices. It is also specified that not all conductors have to be connected. The conclusion is that a two-phase disconnection by semiconductors is sufficient to meet the requirements in relevant standards for operation of motor loads. Therefore there is no difference between a contactor breaking all three phases mechanically and a semiconductor motor controller like the MCI. Question: Why does the MCI soft starter only control 2 of the 3 phases?    Answer: From a technical point of view, it is not necessary to control all three phases except for bigger motors where a high starting torque is important. The un-controlled phase will “follow” the other two phases and the starting current will be reduced in all three phases. The un-controlled phase current will always be approx. 15% higher than the controlled phases. Question: What is a “thyristor” and what does “LTE” mean?    Answer: "thyristor is a semiconductor. In each of the controlled phases a thyristor pair is used. In a CI-tronic™ component the semiconductor is used as the mains switch with or without a ramp up/down function. Sometimes the semiconductor or thyristor is referred to as a power chip. LTE means low thermal expansion. When a semiconductor is switched, its temperature will change rapidly. It is therefore vital that the materials used in its construction have similar coefficients of expansion to avoid mechanical stresses that could be detrimental to the semiconductor." Question: Why do the MCI 15 and MCI 25 not feature integrated by-pass of semiconductors?    Answer: "An automatic by-pass function would require integration of mechanical relays. This would restrict the MCI application and limit the number of starts per hour. Instead the semiconductor design allows that the conductors stay in circuit also when the motor is running with nominal speed. Furthermore the heat sink design ensures that the MCI can withstand maximum load even at an ambient temperature of 40¢ªC. The maximum load is expressed in the rating index according to EN 60947-4-2: Example with MCI 25: AC-53a: 25A: 8-3:100-3000 AC-53a is the load category for asynchronous motors. 25A is the max. permissible load for the MCI 25. 8-3 means that the start profile can be 8 * 25A = 200 A for 3 seconds. A 100% load factor or 3000 operations per hour is accepted." Question: What does “automatic detection of missing phases” mean?    Answer: "The MCI can detect if a motor phase (load) or supplying phase is missing. In such situations the two LEDs will flash and the MCI will not activate. It will only detect the phase failure in stand-by mode. The MCI should always be connected to a three-phase motor in order to be operated. " Question: What about the fact that the uncontrolled phase always is “live” on the motor terminal box?    Answer: Even with the semiconductor switched off, it is possible to measure a voltage on the motor terminals. Therefore it would not make any difference if all three phases had been switched off. The situation is the same with all solid-state controllers and frequency converters. In order to work on the motor terminals, the control device (soft starter or contactor) must be switched off anyway, for example with a circuit breaker type CTI. This is also relevant for a contactor, even though the mains are isolated Question: What is the control voltage?    Answer: This is the voltage used to pull in the main contactor, for instance you may be using 3 phase electricity of 415V through the main contactor to start a motor, but the voltage you use to switch the contactor to start this motor may only be 24V or even 230V, it is this which is the control voltage. Question: Can I buy a C 6?    Answer: "The C range of contacts has now been replaced by the CI range of contactors – typically if you have a C 6 then this can be replaced by a CI 6. This is the same for all the contactors, except for the C 10, for which we would recommend the CI 12 as a replacement. Note: Most of the old range of contactors had built in auxiliaries, now the auxiliaries will have to be purchased separately." Question: Why is there a necessity for a fourth pole?    Answer: Most circuits have three phases. On some, usually smaller, systems, it is desired to break the neutral wire as well as the three “live” phases. Danfoss contactors provide this option up to and including CI 15. Question: What is a pole?    Answer: Pole' is the term used here as shorthand for the pair of contacts which makes or breaks one phase only. Most contactors control three phases; so can be called “three pole”. Some have a fourth set of parallel main contacts which can be use to make or break the neutral wire AS WELL: please note that YOU MUST NOT SWITCH THE NEUTRAL ALONE. Question: I need a spare part for my product. Do you have that?    Answer: Please see the relevant accessories sections in our internet product catalogue, which will list all available spare part options for your market. Question: Where can I find approvals and certificates for Danfoss products? E.g. do you have a PED certificate for KP7W?    Answer: You can find product approvals and certificates for all our products on our internet website. Follow this link to search for documents either by product or by authority: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Documentation/Approvals+and+Certificates.htm Question: Do Danfoss products comply with RoHS directive (Restriction of Hazardous Substances)?    Answer: Yes, all declarations of conformity, including RoHS and WEEE, can be found in our internet product catalogue. Look up the product of your interest and find the relevant document either under the Literature link or the Approvals & Certificates link. Question: How can I connect a CTI circuit breaker with a CI contactor?    Answer: To connect CTI and CI we recommend module CTC: CTC 25-15: Connection module between CTI 25M-MB and CI 6-15 contactors. CTC 25-30: Connection module between CTI 25M-MB and CI 16-30 contactors. Question: I need a star-delta timer type YTI.    Answer: The YTI timer is no longer in production, but we recommend our SDT timer as an alternative. Question: Do you have a soft motor starter for 100 HP?    Answer: MCI 50-3 I-O, the biggest soft starter in our CI-tronic™ range, is for a max. motor power of 40 HP if bypassed during steady state. For even higher rating, we recommend the Danfoss MCD soft starters from the VLT® Drives range. Question: I'm looking for a Danfoss code number and I have not found it in any catalogues?    Answer: Som code numbers are not available for all markets, or it may have been replaced by another number. To resolve the issue, please contact your nearest Danfoss office: http://www.danfoss.com/Contact/Worldwide/ Question: I am looking for a Danfoss product, type USC6000, but cannot find it in your catalogues?    Answer: This product type was previously a part of Danfoss Analytics, and is now part of the company Hach Lange. Question: Could I send you a Danfoss part for repair?    Answer: Danfoss does not have repair departments locally. For warranty or complaints issues, please contact your nearest Danfoss sales office and they will tell you how we handle these issues in your area. Question: Can I get a CI 5, certified for marine use?    Answer: Unfortunately we do not hold any Marine approval for CI 5 mini contactors. As a alternative, we offer contactors in the CI 6-15 range that are approved for Marine use. Question: I am looking for a pump, type APP?    Answer: This product is marketed by Danfoss High-Pressure Systems (Nessie); please see contact options here: http://www.danfoss.com/BusinessAreas/High-Pressure+Systems/Nessie+Worldwide.htm Question: Do you have a contactor, type CL?    Answer: This is not a reference for the Danfoss contactors, the correct type designation is CI. To specify it, you need information like load type, voltage, and current. Please see our internet catalogue for options. Question: I am looking for Danfoss MASSFLO and MAGFLO flow meters?    Answer: This product type was previously a part of Danfoss Flow Division, and is now part of the company Siemens. Question: I am looking for a Danfoss butterfly valve?    Answer: This product is marketed by Danfoss Water Controls; please see contact options here: http://www.danfoss.com/BusinessAreas/Water+Controls/ Question: Can you deliver your products wordwide?    Answer: Yes, we have own distribution centres across the world, working together with more than 100 distributors and agents. You can see your nearest distributor or Danfoss office here: http://www.danfoss.com/Contact/Sales_and_Services/ Question: Do you have a complete catalogue showing all your products?    Answer: Our internet product catalogue is the most extensive information source: http://www.danfoss.com/Products/Categories/ Besides these products, Danfoss also produces customer-specific products and solutions that are not visible in the catalogue. Please contact your nearest Danfoss office to discuss your needs and how we can meet them. Question: Can you deliver products exclusively made for us?    Answer: Yes, we have the possibility to develop products that are unique for one customer subject to individual agreements. The products may differ in appearance, technical features or packaging. Please contact us to discuss your requirements. Question: Which distribution channels does Danfoss use?    Answer: Danfoss makes use of different channels, including distributors, to suit the markets' needs. An increasing number of our customers use our web ordering and EDI e-commerce solutions. Question: Can I review your stock online?    Answer: Yes. By using Danfoss web-ordering, you can check product availability. Please contact Danfoss to get access to web-ordering. Question: Where can I find technical drawings of Danfoss products?    Answer: Dimension and function drawings of our products are often part of the products' technical leaflets. In our internet product catalogue (http://www.danfoss.com/Products/Categories/), find the product of your interest, then follow the Literature link to see avaliable items. Question: Do you have Solid State Relays in your program?    Answer: Yes, the ECI electronic contactors 1, 2 and 3 phase switches. For more details please see our internet catalogue. Question: I have mounted a Softstarter MCI C on my air compressor - why doesn't it work?    Answer: For your compressor, you should use a standard MCI softstarter where you can adjust the start parameters. The MCI C compressor soft starters are specifically designed for soft starting of 3-phase compressors and have default settings. Question: How do I select the correct soft starter?    Answer: First you have to keep in mind that a soft starter reduces the starting current. You must select a softstarter which supplies adequate current to ensure smooth operation of the motor or application. Please consider the number of starts per hour and the ambient temperature and also the necessary monitoring and control functions. Question: Where do I direct commercial or technical questions?    Answer: Danfoss worldwide sales and services is available here: http://www.danfoss.com/Contact/Sales_and_Services/ Your nearest Danfoss office will be able to answer your question, or have it directed to the appropriate expert. Question: Do you have local stock?    Answer: This depends on the country and product concerned. Our logistics are set up to achieve competitive and reliable delivery perfomance for our customers. Question: Where can we find your data sheets?    Answer: All relevant literature, including technical brochures, are available on our Web site: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Documentation/Industrial+Automation+Literature.htm Question: Do you have local websites in my language?    Answer: Yes, please see http://www.danfoss.com/ and then use the "Local sites" option in the top righthand corner. Question: Is it possible to place orders online?    Answer: Yes, you can place orders and access order information online. Please contact Danfoss to get access to web-ordering. You can see the benefits of Danfoss web-ordering at http://www.danfoss.com/Products/ebusiness/ Question: Can you give me some key figures on danfoss?    Answer: If you are looking for number of employees, sales companies, turnover etc., you will find updated information here: http://www.danfoss.com/AboutUs/FactsAndFigures/ Question: Does Danfoss operate globally?    Answer: Yes. More than 100 Danfoss sales companies and more than 100 agents are spread across the world, making Danfoss nearby, always. Question: Is Danfoss a German company?    Answer: No, it is a globally acting group with headquarters in Denmark. Question: I am looking for a hydraulic oil pump?    Answer: Hydraulic oil pumps are part of the product programme of the separate company Sauer-Danfoss. Question: I am looking for a CI 4 minicontactor?    Answer: The CI 4 range is out of production, replaced by the new and more advanced CI 5. Please see our internet catalogue for details. Question: When is it recommended to use electronic contactors type ECI?    Answer: It is recomend to use ECI electronic contactors instead of electromechanical contactors, when long life - up to 50 times more than standard contactors - and no-limited starts per hour is demanded. Question: Do soft starters have any internal protection?    Answer: No, they do not have any protection. You need to use a circuit breaker before the soft starter, or use fuse and contactor with thermal relay, which ensures protection againts overloads and short-circuit. Question: What is maximum overload current of soft starters?    Answer: Maximum overload current for soft starters is 6xIn or 8xIn (where In is nominal current). For more details (duty ratio, number of cycles/hour, time between each start operation) please refer to overload current profile in our technical brochure. Question: I have a 21 kW motor application with star-delta starter, how can I change to softstarter in the cheapest way?    Answer: We recommend the MCI 40 with inside-delta connection. Question: How can I control speed of fans with 1-phase motors?    Answer: You can use ACI 30 of CI-tronic™ series, which control speed of motors via a 0-10 V or 4-20 mA signal. The application is commonly used for fans installed in condensing units. Question: It the contact 037H0115, type CB-DC available?    Answer: No, it is replaced by the CB-LB (037H0114), which also has a late break function (not "extra late break"). This auxiliary contact works with more voltages, not only with DC. Question: What is trip class?    Answer: Trip class is the expression used in connection with the designation and current settings of overload relays and soft starters. The most popular are 10A and 10 trip classes. They are suitable for light/standard duty applications. Trip class corresponding to minimum overload current withstand time. For example: Class 10A = overload ratio 8 (8 times nominal current) for 1.6 seconds; Class 10 = overload ratio 8 for 3 seconds. Question: What is the Burst Firing mode on ACI and ECI electronic contactors?    Answer: The Burst Firing mode means that softstarter takes turns in suppling full sin cycles to the load. The load will be supplied full ON than OFF in turns. Question: Why is our delivery delayed, when I saw that the delivery date is confirmed for 2 weeks in e-commerce?    Answer: Reasons for late delivery could be production problems from Danfoss or incompliance with the payment terms from your side. You can always check the status of your order on our e-business system to see updated confirmation date or a message to contact Danfoss in case of late payment. Question: What is the maximum starts and stops of my TCI softstarter?    Answer: The TCI softstarter range has unlimited start/stop operations per hour. Question: Where can I find some technical information about your products?    Answer: Please see our online product catalogue: http://www.danfoss.com/BusinessAreas/IndustrialAutomation/Product+catalogue/IA+product+catalogue.htm Question: Does a thermal overload relay provide full protection of the motor?    Answer: A thermal overload relay equipped with bimetals is a relatively small, yet reliable appliance to protect electrical motors against: –mechanical overload, –asymmetrical operation, –phase failure. To provide protection against short circuit current you should use fuses. For full protection of the motor, we recommend CTI circuit breakers. Question: Which type of thermal overload relay should I choose for contactor CI 20?    Answer: Please find below thermal overload relay range and related contactors: •TI 9C-5 – fits CI 5- ; Range 0.1-9.2 Amp. •TI 16C – fits CI 6 – CI 16; Range 0.1-16 Amp. •TI 25C – fits CI 20-CI 25; Range 15-25 Amp. •TI 30C – fits CI 30; Range 24-32 Amp. •TI 80 - fits CI 32 –50; Range 16 – 63 Amp. •TI 80 - fits CI 61 –86; Range 42-80 Amp. •TI 86 - fits CI 61-86; Range 74-85 Amp. TI 25C is dedicated for CI 20. Question: What are mirror contacts and mechanically linked contacts?    Answer: These contacts provide reliable monitoring of the status of the contactor. This means that an NC auxiliary contact cannot be in closed position simultaneously with the NO main contact(s) of a contactor. We have feedback if the main contacts welds. For more data, please see IEC Standards: - Mechanically linked contacts in CI 5 – according to IEC 60947-5-1 Annex L, - Mirror contact between contactor contacts CI 5 and aux. contact block CBN - according to IEC 60947-4-1 Annex F. Question: What are bifuctureted H-shaped contacts?    Answer: Bifuctureted, H-shaped contacts are specially designed contacts that enable switching signals down to 15V/2 mA. They are mounted in control relays CI 5-2 and in auxiliary contacts CBD. Mini contactors CI 5-5, CI 5-9, CI 5-12 have standard contacts. Question: How can the operation of the CI 210 EI coil be controlled?    Answer: The operation of the coil can be controlled in two ways by an electronic circuit: I. "EI" Interface mode II. "E" Standard mode The location of the joint is essential and it determines the way in which the coil is controlled. It means that you can operate contactor from a PLC when you use "EI" Interface mode. It works like this: Until you supply 24V DC on B+ B- the coil is de-energised although there is supplied net voltage on A1 A2. Question: Can Danfoss provide a 24V/50Hz coil for a CI 180 contactor?    Answer: A 24V/50Hz coil is not available as a spare part and not available as a standard code number. However, if you have a significant need for a CI 180 with 24V/50Hz coil, please contact your nearest Danfoss office. Question: What is the difference between MCI xx and MCI xx C families?    Answer: There is almost no hardware difference between the MCI xx and MCI xx C families, but the MCI xx C series has factory-fixed settings for compressor applications. Question: Why do we bypass the soft starter in steady state?    Answer: Bypass is important when the soft starter is working in temperature above 40 °C – in this case you don't have to reduce load or duty cycle when the soft starter is bypassed in steady state. Moreover bypass eliminates the electromagnetic disturbances EMC during the full voltage operation. Question: Does the MCI-CH have some protection against phase change?    Answer: No, MCI-CH has no phase change detection implemented. Question: What is the difference between the AC-3 and AC-4 categories?    Answer: The AC-3 category is dedicated to squirrel-cage motors; starting, disconnecting while running, whereas AC-4 is dedicated for control of squirrel motors, starting, plugging, inching. When we perform laboratory tests AC-3 means that make current is 6 x In (nominal current), brake current is 1 x In. AC-4: make current 6 x In, brake current 6 x In. Question: What is the difference between the "AC-" Utilization Categories and why they are so important?    Answer: To define the conditions for which the contactors should be sized, the utilization categories have been implemented by IEC. Most common are: - AC-1: Non inductive or slightly inductive loads. - AC-3: Squirrel-cage motors: starting, disconnecting while running. - AC-4: control of squirrel motors, starting, plugging, inching - AC-15: Switching electromagnets (e.g. coils in control circuits). The same contactor can withstand 40A for AC-1 but only 27A for AC-3 (CI 16). When electricians talk about technical data of contactors, they usually think of AC-3, being the most "popular" utilization category. Question: What is the Utilization Category for contactors used for switching tubular light bulbs?    Answer: Tubular light bulbs are AC-5 load category. Question: How should I interpret MCI rating index AC-53b?    Answer: AC-53b:6-6:30 means: Motor controller rating with bypass contactor; overload capability 6-6 - 6x nominal current for 6sec; 30 means time in seconds between each start operation. Question: How should I interpret MCI rating index AC-53a?    Answer: AC-53a:6-5:100-480 means: Motor controller rating without bypass contactor; overload capability 6-5 - 6x nominal current for 5sec; duty ratio in % - 100%= continuous operation; 480 means number of cycles per hour. Question: What does AC-53a and AC-53b stands for and what is a difference?    Answer: There are two basic utilization categories for AC semiconductor motor controllers (MCI xx): AC-53a and AC -53b. AC-53a describes operational capabilities of controlling squirrel cage motors by semiconductor controller (MCI) AC -53b describes operational capabilities of controlling squirrel cage motors by semiconductor controller (MCI) bypassed during running. Note: The means of bypassing controller may be integral with the starter or installed separately Question: Can I get quality control plans/process flowcharts/material specifications/FMEA for Danfoss products?    Answer: No, this is confidential information which cannot be shared outside Danfoss. Rare exceptions are cases of special legal agreements between Danfoss and the other company. Question: Can you send me literature, brochures or catalogues on your products?    Answer: We appreciate your interest and will happily send you an overview of our offering in print. Please contact your local Danfoss office or e-mail us on ia@danfoss.com, describing your interest and application. Question: I placed an order through e-commerce. Could you please check the delivery dates and inform me the earliest possible delivery?    Answer: Delivery dates are supplied in the e-commerce system and based on Danfoss standards. If the confirmed delivery date is not acceptable, please contact Danfoss through e-mail or telephone. Question: Can I download product approvals & certificate from the Danfoss websites?    Answer: Yes, in our internet product catalogue, all product approvals & certificates are listed. If you are unable to local a specific document, please e-mail or call us. Question: Where can I locate the ordering number on a TI 16C?    Answer: There is no code number printed on the product itself, but the code number can be defined by the current range printed on the scale. The selection of thermal overload relay must be based on the motor full load current and the method of starting: direct or star-delta start.