The Allen-Bradley 150-F251NBD is a 3-phase soft start motor control module manufactured by Rockwell Automation. This motor controller belongs to the SMC-Flex series and has a voltage range of 200 Volts to 480 Volts AC. The 150-F251NBD has an AC coil input voltage range from 100 Volts to 240 Volts at a nominal frequency of 50 Hertz (Hz) and an average current rating of 251 Amperes (Amps). The contact rating of this starter is a range of 75 - 250 kilowatts and the power range is approximately 75 kilowatts (kW). The 150-F251NBD has a programmable contact configuration. Normally, this will consist of one closed contact and one open contact.

The 150-F251NBD has a range of safety features, including an SCR bypass/run contactor to guard against inrush current. It also possesses an electronic motor overload protection system and configurable ground fault detection. The qualified operator can configure this protection to best suit the application, either activating an automatic ground fault trip or an alarm on ground fault detection, or both of these safety features at the same time. However, it is necessary to install an external sensor in order for ground fault detection to function properly with the 150-F251NBD. This component is vulnerable to electrostatic discharge (ESD), which means that it is absolutely vital to observe proper ESD control and minimization measures during installation. The 150-F251NBD has a wider temperature range than some of its counterparts because of the open enclosure type which it makes use of. This enables it to operate safely within the whole temperature range of 0C to 50C.

The Allen-Bradley 150-F251NBD is equipped with both a keypad and an LCD, or liquid crystal display. These two features make up the primary operator interface used to interact with the product itself. The keypad consists of only five (5) keys. The keys included on the keypad are as follows: one (1) "escape," "select," and "enter" key. There are also two (2) navigation keys which are "down" and "up." Since this keypad is not equipped with numerical keys, to program values into the device, all one needs to do is press the "enter" key to edit, then use the "select" key to move over to the digit that needs to be modified. From there, use the arrow keys, or "up" and "down" keys, to scroll through the digits. The Allen-Bradley also utilizes an LCD display as to display any and all information. This LCD display has three (3) viewable lines that allow for sixteen (16) characters to be shown. Additionally, this liquid crystal display is backlit so that it may be viewed in any lighting. 

The ambient temperature when storing the Allen-Bradley 150-F251NBD should be maintained within the range of minus twenty (-20) and plus seventy-five (+75) degrees Celsius. This temperature range is equivalent to minus four (-4) and plus one hundred sixty-seven (+167) degrees Fahrenheit. The non-condensing, relative humidity range when storing this product should stay within 0 (zero) and 95 (ninety-five) percent. Additionally, be sure to store this device in an area that is both clean and dry. Do not store it in an area that it may be exposed to harmful atmosphere.