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MMUs

Cabinet monitors for Caltrans, NEMA & ITS cabinets.

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Critical Safety Monitoring for Signal Operations

Malfunction Management Units (MMUs) continuously monitor traffic signal controllers for conflicts, voltage issues, and configuration errors. If a fault is detected, the MMU automatically triggers a fail-safe mode—usually flashing red—to protect drivers and pedestrians from unsafe signal conditions.

Compliance with Traffic Safety Standards

MMUs are required components in modern signal cabinets, meeting strict industry standards such as NEMA or ATC. Their built-in diagnostics, watchdog timers, and error logging functions help ensure compliance and allow traffic agencies to quickly identify and resolve issues.

Built for Reliability and Fast Recovery

Designed for 24/7 reliability, MMUs feature durable construction and self-checking mechanisms to prevent false signals and system failures. When combined with modern controllers and software, they support faster system recovery, minimizing downtime and maximizing intersection safety.

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MMUs

Best-Selling Solutions

Browse our most frequently requested MMUs, available for immediate purchase or custom manufacturing.

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EDI 210C Conflict Monitor for Caltrans cabinets

Designed to provide the basic monitoring requirements for Caltrans Type 170 Output Files.

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EDI 2010 Series SIGNAL MONITOR UNITS FOR CALTRANS CABINETS

Utilizes enhanced monitoring functions to increase cabinet fault coverage, providing additional assurance that cabinet equipment malfunctions will be detected and diagnosed properly.

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EDI 2018 Series SIGNAL MONITOR UNITS FOR CALTRANS CABINETS

Enhanced monitoring functions to increase cabinet fault coverage, providing additional assurance that equipment malfunctions will be detected and diagnosed properly.

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EDI AMU-214 AUXILIARY MONITOR UNIT FOR ITS CABINETS

Provides the voltage and current data acquisition function of the cabinet monitoring system.

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EDI CMU-212 CABINET MONITOR UNIT FOR ITS CABINETS

Intended to operate with the AMU-214 Auxiliary Monitor Unit to form a compact and modular cabinet malfunction management system for the ITS Cabinet.

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EDI MMU2-16LE Series MALFUNCTION MANAGEMENT UNIT FOR NEMA CABINETS

Use the built-in Setup Wizard to quickly and accurately configure the SmartMonitor® to the exact requirements of the cabinet and intersection.

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EDI MMU-16E MALFUNCTION MANAGEMENT UNIT FOR NEMA CABINETS

Incorporates many of the features of a TS1-1989 Conflict Monitor Unit along with additional enhanced monitoring, display, and trouble shooting functions.

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EDI NSM-E Series NEMA STANDARD MONITOR ENHANCED SERIES

Provides technicians with full intersection display and powerful monitoring and trouble-shooting tools to ensure cabinet malfunctions are detected, diagnosed, and repaired with confidence.

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EDI SIU-2218 SERIAL INTERFACE UNIT FOR ATC CABINETS

Performs the interface between Serial Bus #1 of the Controller and the Input Assembly, Output Assembly, and other devices in an ATC cabinet.

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EDI SSM-LE Series SIGNAL SEQUENCE MONITOR UNITS FOR NEMA CABINETS

Full Intersection LCD display and event log recording capabilities equip technicians with detailed and accurate information to ensure cabinet malfunctions are detected, diagnosed, and repaired with confidence.

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EDI MonitorKey DATA KEY PROGRAMMING TOOL

Replaces the traditional conflict monitor Programming Card and eliminates the need for mechanical switches, jumpers, and diode cards.

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What Our Clients Say About Working with ATS Traffic

Read authentic reviews from businesses and organizations
we’ve served throughout Canada.

Very efficient and nice people working there.

Cory Farley

Google Review, Regina

We rent Signage all the time and ATS has always come through, especially on short notice, emergency work.

Jody Reimer

Google Review, Winnipeg

Very, very friendly and professional staff. I was looking for a very niche item that no where else in town had. Instead of just saying no sorry, they instead went through the hassle of looking through catalogs to see if what I needed could be ordered. They even went as far as to look online and find me a link for what I needed!!! 10/10 recommend.

Ben Harder

Google Review, Langley

I met one of the flaggers and she shared quite a bit of knowledge on flagging laws and took her job seriously… it made me think ATS traffic is a great company to hire when I need flaggers.

D P

Google Review, Langley

Crews are amazing to work with, and the staff are always there to answer any questions you have and to assist you.

MeRTo

Google Review, Edmonton

Great customer service staff.

Mike L

Google Review, Edmonton

Amazing to deal with! Very friendly people.

Jennifer Kellar

Google Review, Brandon

I always look forward to picking up equipment at ATS, always very helpful!

Karl Jones

Google Review, Calgary

These guy’s rock. Good service and excellent to deal with.

Makhayla

Google Review, Calgary

ATS Traffic’s clear and timely communication and commitment to road safety sets it apart from its competitors.

Ashley Bilodeau

Google Review, Edmonton

Fast, easy ordering. Pretty much do anything to get the job done. Great attention to safety while working in the street.

Skyler

Google Review, Edmonton

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