Allen-Bradley and Rockwell Automation manufacture the 500-DOB920 NEMA AC/DC Contactor as part of the Bulletin 500 Contactors series. Like many other contactors in this line of products, the 500-DOB920 Contactor has NEMA size of 3, and it comes with no enclosure type or with the open-style NEMA enclosure that makes it easy to install. It also features nominal coil voltages of 440 Volts and 480 Volts at 50 Hertz and 60 Hertz frequencies, respectively. The other notable features of the 500-DOB920 Contactor include 2 power poles and one normally open auxiliary contact. Some of the 500 series options that are not included in this AC/DC contactor include a surge suppressor rated for coils of 120 Volts AC and 240 Volts AC and a Normally Closed (NC) auxiliary contact. However, this device can be ordered in different options for flexibility and convenience in different applications, and that is why it is available as its individual components or in a complete modular kit. 

As a modular kit, the 500-DOB920 NEMA AC/DC Contactor comes with selectable options that are available separately like the number of power poles it comes with, the coil voltage feature and rating, and many others. It also includes a top wiring kit, a base contactor, and a load side terminal shield. The Allen-Bradley 500-DOB920 AC/DC Contactor is certified and approved for compliance with the UL, CSA, ABS, CE, and IEEE standards. The base contactor size of this device is size 3 and it features a continuous current rating of 90 Amps. All the power connections of this contactor are located on the top side to enable wiring convenience. This contactor can also be field-wired to allow it to be used with both the 3-phase and the single-phase applications. There are devices from the same series with NEMA sizes 00, and sizes 5 to 9 which are only available as factory-assembled units and not as kits or separate components like the 500-DOB920 NEMA AC/DC Contactor.