Thermistor Trip Protection Relays

DescriptionDIN rail mounting protection relays for use in single and three phase systems. Available in 55mm x 112mm or 100 x 112mm DIN rail cases.ApplicationFor over protection, under protection and combined under & over protection available in AC current AC voltage & frequency versions. Millivolt trip, DC voltage trip, Reverse Power, Phase sequence & Phase balance relays also available in our extensive range of protection relays.Selection GuideM200-TTAAutomatic resetM200-TTMManual resetTypical ApplicationsThe M200 thermistor trip accepts positive temperature coefficient inputs. Typically used to monitor temperature in motor windings. When the thermistor is below its predetermined temperature the resistance is low and the M200-TTA/TTM relay is energised. A green LED indicates the safe condition. When the temperature exceeds the predetermined temperature the resistance of the thermistor rapidly increases, this increase in temperature is detected by M200-TTA/TTM and the relay is de-energised. The M200-TTM is manually set, once the relay has de-energised it will stay de-energised regardless of the temperature being monitored. The relay can only be reset via the reset push button on the front of the unit. The M200-TTA automatically resets once the temperature has dropped below the trip point. A yellow LED is provided to indicate the condition of the power supply.Technical SpecificationsINPUTPositive temperature coefficient thermistors:Sensors can be connected in series but 1500Ohms must not be exceededTrip Point2500-3500 OhmReset Point1500-2300 OhmTotal resistance of sensor loop1500 Ohms max at nominal temperatureDifferentialFixed 5%RepeatabilityBetter than 5%RESETM200-TTAAutomaticM200-TTMManual via push switch on front of productAUXILIARYA.C. Voltage115/230/400V±25%/45-65Hz/2VAD.C. Voltage24 volt(±20% / non-isolated)< 3 wattWEIGHT&CASEApprox 0.3kg. 55mm caseOrdering InformationProduct CodeAuxFreqOptionM200-TTA230V50HzOptions1A.C. auxiliary in range 57.7 to 480 volts2Calibration at temperature other than 23CConnection Diagrams

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