7.11.5 VLT® Sensor Input Option MCB 114The sensor input option card MCB 114 can be used in the following cases:• Sensor input for temperature transmitters PT100 and PT1000 for monitoring bearing temperatures.• As general extension of analog inputs with one additional input for multi-zone control or differential pressuremeasurements.• Support extended PID controllers with I/Os for set point, transmitter/sensor inputs.Typical motors, designed with temperature sensors to protect bearings from being overloaded, are fitted with 3 PT100/1000temperature sensors; 1 in front, 1 in the back-end bearing, and 1 in the motor windings. The VLT® Sensor Input Option MCB114 supports 2- or 3-wire sensors with individual temperature limits for under-/overtemperature. An auto-detection ofsensor type PT100 or PT1000 takes place at power-up.If the measured temperature is either below the specified low limit, or above the specified high limit, the option generatesan alarm. The individual measured temperature on each sensor input can be read out in the display or by readoutparameters. If an alarm occurs, the relays or digital outputs can be programmed to be active high by selecting [21] ThermalWarning in parameter group 5-** Digital In/Out.A fault condition has a common warning/alarm number associated with it, which is Alarm/Warning 20, Temp. input error. Anypresent output can be programmed to be active in case the warning or alarm appears.7.11.5.1 Electrical and Mechanical SpecificationsAnalog InputNumber of analog inputs 1Format 0–20 mA or 4–20 mAWires 2Input impedance <200 ΩSample rate 1 kHz3rd order filter 100 Hz at 3 dBThe option is able to supply the analog sensor with 24 VDC (terminal 1).Temperature Sensor InputNumber of analog inputs supporting PT100/1000 3Signal type PT100/1000Connection PT 100 2 or 3 wire/PT1000 2 or 3 wireFrequency PT100 and PT1000 input 1 Hz for each channelResolution 10 bitTemperature range-50–204 °C-58–399 °FGalvanic IsolationThe sensors to be connected are expected to be galvanically isolated from the mains voltagelevel IEC 61800-5-1 and UL508CCablingMaximum signal cable length 500 mSpecifications Design Guide172 Danfoss A/S © 09/2014 All rights reserved. MG20N60277
