Danfoss VLT AutomationDrive FC 300 Design Manual

Also see for VLT AutomationDrive FC 300: Instruction manual Operating instructions Design guide Service manual Operating instructions

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Danfoss VLT AutomationDrive FC 300 Design Manual Manual pdf 56 page image

3.12.2 Safe Torque Off Operation (FC302 only)The Safe Torque Off function of FC 302 can be used forasynchronous, synchronous, and permanent magnetmotors. It may happen that 2 faults occur in the frequencyconverter's power semiconductor. When using synchronousor permanent magnet motors, this may cause a residualrotation. The rotation can be calculated to Angle=360/(Number of Poles). The application using synchronous orpermanent magnet motors must take this into consid-eration and ensure that this is not a critical safety issue.This situation is not relevant for asynchronous motors.3.12.3 Liability ConditionsLiability conditionsThe user is responsible for ensuring that personnel knowhow to install and operate the Safe Torque Off function by:• Reading and understanding the safety regulationsconcerning health and safety/accident prevention• Understanding the generic and safety guidelinesgiven in this description and the extendeddescription in the Operating Instructions VLT®Frequency Converters – Safe Torque Off.• Having a good knowledge of the generic andsafety standards for the specific applicationThe user is defined as integrator, operator, service, andmaintenance staff.3.12.4 Additional InformationFor more information regarding Safe Torque Off, includinginstallation and commissioning, refer to the OperatingInstructions VLT® Frequency Converters – Safe Torque Off.3.12.5 Installation of External Safety Devicein Combination with MCB 112If the ex-certified thermistor module MCB 112, which usesTerminal 37 as its safety-related switch-off channel, isconnected, then the output X44/12 of MCB 112 must beAND-ed with a safety-related sensor (emergency stopbutton or safety-guard switch) that activates Safe TorqueOff. This means that the output to Safe Torque Offterminal 37 is HIGH (24 V) only if both the signal from MCB112 output X44/12 and the signal from the safety-relatedsensor are HIGH. If at least 1 of the 2 signals is LOW, thenthe output to Terminal 37 must be LOW, too. The safetydevice with this AND logic itself must conform to IEC61508, SIL 2. The output connection of the safety devicewith safe AND logic to Safe Torque Off terminal 37 mustbe short-circuit protected. Illustration 3.40 shows a Restartinput for the external Safety Device. This means that in thisinstallation, set [7] or [8] 5-19 Terminal 37 Safe Stop. Referto the MCB 112 Operating Instructions for further details.130BA967.1112111098765432137203332292719181312DI DISIL 2Safe StopDigital Inpute.g. Par 5-15PTCSensorX44/Par. 5- 19Terminal 37 Safe Stop Safety DeviceS afe Input Safe OutputSafe AND InputManual RestartPTC Thermistor CardMCB112Non- Hazardous AreaHazardousAreaIllustration 3.40 Illustration of the Essential Aspects forInstalling a Combination of a Safe Torque Off Application andan MCB 112 ApplicationParameter settings for external safety device incombination with MCB 112If MCB 112 is connected, then additional selections ([4]–[9])become possible for 5-19 Terminal 37 Safe Stop (Terminal37 Safe Torque Off).Selections [1]* and [3] 5-19 Terminal 37 Safe Stop are stillavailable but are not to be used as those are for instal-lations without MCB 112 or any external safety devices. If[1]* or [3] 5-19 Terminal 37 Safe Stop should be selected bymistake and MCB 112 is triggered, then the frequencyconverter will react with an alarm ”Dangerous Failure[A72]” and coast the frequency converter safely withoutautomatic restart.Selections [4] and [5] 5-19 Terminal 37 Safe Stop are onlyselected when MCB 112 uses the Safe Torque Off. Ifselections [4] or [5] 5-19 Terminal 37 Safe Stop are selectedby mistake and the external safety device triggers SafeTorque Off, the frequency converter reacts with analarm ”Dangerous Failure [A72]” and coasts the frequencyconverter safely without automatic restart.Product Introduction VLT® AutomationDrive FC 300 Design Guide 90-1200 kW54 MG34S202 - Rev. 2013-08-1933