1771-OFE1K

The Allen-Bradley 1771-OFE1K is a conformal-coated PLC 5 analog output module. Conformal coating protects the module from humidity and contamination. It is a voltage module which converts 12-bit binary or 4-digit BCD (binary-coded decimal) values to analog signals with its 4 outputs. It has 3 selectable voltage ranges of 1 – 5V DC, 0 – 10V DC, and ±10V DC. Peripheral devices such as motor speed controllers, valve positioners, recorders, or signal converters can be connected to the output. The 1771-OFE1K uses block transfer programming for data transfer. Write Block Transfer moves data up to 13 words away from the processor to the module for DA conversion in just one scan and Read Block Transfer moves 5 words of data from the module to the processor for debugging. The 1771-OFE1K module has 4 1000V individually-isolated differential outputs. It requires a power of 1.4A at 5V which is supplied from the I/O chassis backplane, thus no external power supply is needed. It has a channel update time of 8ms per 4 channels for BCD and 1.6ms per 4 channels for Natural Binary. It has a maximum power dissipation of 7.9W and maximum thermal dissipation of 26.9 BTU/hr. The 1771-OFE1K includes a wiring arm to replace the module without disconnecting the wires. It can be installed in any slot in a 1771 I/O chassis and keying bands must be snapped between 10-12 and 26-28 for fixing that slot. The 1771-OFE1K module can convert raw data to measurement and engineering units such as °C, °F, gallons/minute, and pounds/square inch. For diagnostics, it performs a self-check at start-up. If a fault occurs, the red fault LED activates and the green power status LED remains off. The 1771-OFE1K has 1500V optoelectrical isolation which protects the system from overvoltage situation.