1771-NB4S

The Allen-Bradley 1771-NB4S Analog Module is an intelligent block transfer module which connects analog signals to the programmable logic controller. It is a 4-channel module with two 4-20mA inputs, and two 0-25mA current outputs, and the module draws a backplane current of 1.4A. The module has an input module that supplies a loop power of 4-20mA, and an output current range of 0-25mA. The 1771-NB4S has an output resolution of 3.2µA per bit (13 bits unipolar) with an output impedance that is less than 1 megaohm, and a drive capability of 25mA at 700ohms. It has output overvoltage protection at 140V AC (RMS), and it has an OFFSET drift of ±1µA per oC with a GAIN drift of ±50 ppm per oC. The 1771-NB4S module’s maximum update time is 25ms and it uses a digital-to-analog (D/A) converter with a loaded dependent full-scale settling time of 500µs. It has an accuracy of 0.01% at 25 oC and of 0.08% at 25 oC and it requires field calibration with a calibration setting of 0.5mA/22mA, and it has a 1-year calibration interval. It has a rampling value of 0.16mA per second and 32mA per second for 1% and 200% FSR. The 1771-NB4S is fitted into a single slot of the 1771 I/O chassis and is keyed to the chassis by connecting top connectors between pins 26 and 28, and pins 32 and 34. The 1771-NB4S offers input channels and backplane connections tested at 1200V DC for 1s, and it is built to withstand a voltage of 1000V DC, between the input and output channels and between the input and backplane connections. Its functional temperature ranges between 0 and 60 oC at 5-95% non-condensing relative humidity.