Dear @MathieuGuillot, it seems that @sesa25008_bridg question (... a more conservative way to define this cooperation in a general approach) is similar to what I would like to ask. Does Schneider carry out tests for each pair/combination of protection device/equipment (starter) to confirm coordination level or test procedure is done only for specific sizes of device/equipment followed by a calculation procedure which gives the result for the other pairs/combinations ? If so, could this calculation procedure be available for sharing ? If this calculation procedure is not available could you send guidelines for a conservative selection ? Thank you
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I don’t see any risk of major malfunction during operation at 380Vac nominal voltage for a system designed for 400Vac. Indeed large majority of equipment designed for 400Vac are applicable to 380Vac. But as we say “The Devil is in the Details.”
To ensure proper functioning of the future installation you should check few things:
I suggest to start your analysis by checking the tolerances of the supply voltage in both locations. What is the minimum voltage you may have today and what is the minimum voltage you may have tomorrow. If the tolerance of the supply in your new location is -10% you have to check that your production line can withstand temporary operation at 340Vac LL 200Vac LN. But may be your existing system is 400Vac -10% and the future 380Vac – 5% …
When you know the minimum voltage you can reach in the future, global efficiency and performance will depend on the type of loads.
Some loads have a current proportional to the voltage (Typically resistor like heaters ..) for this loads the voltage reduction will means current reduction. From process point of view it will means longer operation for an heater to reach the same temperature.
Some loads have a constant power, so voltage reduction means current increase. (Typically electronic converters such as variable speed drive, electronic power supply …) In that case there is no consequence on the process itself, but the supply and electrical equipment (cables, circuit-breaker, contactors…) upstream such loads need to handle the increase of the current. (Risk is overload trip for instance)
Some loads have a more complex relationship between voltage and current : typically induction motors. Reduction of the voltage implies reduction of the torque applied to the mechanical loads. This may have an impact on your process (less debit for pump, less pressure for a juicer …) depending on the type of mechanical load. Here again at 380Vac nominal it shall not have significant consequence as 380V is in the tolerance of a 400Vac system. But if the 380Vac system is running at – 5 or -10% you may start to have consequences on your process.
Some equipment have a “black and white behavior” according to voltage : typically relay / contactors .. that will switch off below a limit. You have to check that this type of equipment are able to operate as expected in the full range of voltage.
Hope it helps.
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Hello, such a small motor can have very high inrush current. Therefore the problem of starting will be the voltage drop imposed on the motor already running in parallel. I suppose that the design is standardized, as in the beginning of the message it is said to be a typical practice. Otherwise motor starting may need to be performed with a progressive starter, soft-starter or even to check with VSD, where you can potentially benefit from energy saving.
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The ability of a circuit breaker to operate in IT earthing system is covered by the normative Annex H of IEC/EN 60947-2.
All our product TeSys GV and ComPact NSX are compliant to this Annex H for all operating voltages (if not they would be marked with a strikethrough IT). Compact NSX HB1 for instance is suitable for 690V 65kA IT application. (They are used often in 690V Marine application that is 100% IT for instance)
For Contactor there is no special requirement according to earthing system. Circuit-breaker & Contactor coordination tests according to IEC/EN 60947-4-1 are as well not depending of earthing system.
Some additional requirment may exist in some countries. Do you have some special requirments in addition to compliance with IEC/EN 60947-2 and IEC/EN 60947-4-1 in your project ?
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TH110 or more generally "Thermal monitoring" and HeatTag are two different principles. TH110 is a battery free wireless temperature sensor for busbar or large cables. Installing and connecting to an upper system these sensors in various location of an MV or LV cubicle allow to follow in real time the temperatures of connections. This solution provide an accurate information of the real time temperature status of the equipment. it allow also to run algorithm corraleted with current measurement to detect abnormal heating. It can avoid infrared inspection. HeatTag is a smart sensor analyzing the air in the cubicle, it detect particles released by insulation materials when reaching abnormal but not yet dangerous temperature. (it "smells" the heat). The use of one or the other or a combination of both is the result of risk analysis and ratio benefit / cost analysis. As a rule of thumb in switchboard with low load profile and/or limited number of busbar connections the risk of hot spot due to bad connection on busbar is low, the monitoring of cables connections of feeders with HeatTag only is a good compromise. On the opposite in Switchboard with a heavy load profile or large switchboard with complex busbar arrangement with multiple busbar connections, monitoring the busbars connection with dedicated sensor is very relevant. HeatTag can then be used additionally to monitor feeders cable connection. Mathieu Guillot
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