The Allen-Bradley 1764-MM1RTC is a model from the MicroLogix 1500 Controllers line. The MicroLogix 1500 series features controllers for industry that are made of the following parts: base units, accessories and processors. This module is an accessory. The 1764-MM1RTC combines the features of the 1764-MM1 and 1764-RTC modules. It provides the features of a real time clock and a memory module to the user. The RTC is provided with an internal non-replaceable battery, with a nominal duration of 5 years. A battery low indicator lies on the module and will provide the user a feedback on the battery. This indicator turning on means that the battery may fail in within 14 days and that the module should be replaced. If valid data is sent to the real-time clock from the controller, the new date and time will take place immediately. The module can be plugged in the controller at any time. The RTC function will begin as soon as the module is detected, while the memory module function will either need for the controller to be in a non-operational state or to carry out a reboot or power cycle. The removal of the module will lead the programmable controller to write zeros onto the Real Time Clock function file. The memory module component of the module will provide 8 kilobytes for user applications in order to carry out application downloads, transfers or uploads. With the memory module, the user can exploit many features such as program compare, data file download protection and memory module write protection.

The 1764-MM1RTC comes with two output ports – the first being the DC FET port, and the second being the relay port. It supports three different relay base units. You can use the 1764-BXB, the 1764-AWA, or even the 1764-BWA with this module. Furthermore, it is compatible with two different controllers – the first being the 1764-LRP, and the second being the 1764-LSP. Coming with 8 kilobytes of memory storage, this module also features a real-time clock. It belongs to the MicroLogix 1500 series from Allen-Bradley. The clock accuracy might vary depending on the temperature that it is operating in. For instance, if this module is operating at 0 degrees Celsius, the clock accuracy will be anywhere between +34 to -70 seconds per month. When operating at 25 degrees Celsius temperature, the clock accuracy will be +36 to -68 seconds per month.   

The 1764-MM1RTC requires a battery for the real-time clock inside it. However, this battery is not replaceable. As it comes with a 5-year life span, the need to change the battery will be reduced significantly. The battery features a status indicator on its front. It will notify the users 14 days prior to the battery juice depleting completely. 

The 1764-MM1RTC is ideal for appliances that requires time coordination in real-time. This module can supply the controller with all necessary time information such as what day it is, how many minutes have passed since a particular event, and how many seconds before any particular event will. This module can provide security for memory modules and other connected components.