A traffic controller usually sits in a traffic cabinet next to the intersection and controls the lights and pedestrian signals, based on its internal timer, as well as inputs from vehicle sensors and pedestrian push buttons. Controllers are well designed to be safe and redundantly reliable devices. However, the Conflict Monitor Unit (CMU), and the more powerful Malfunction Monitor Unit (MMU), are designed to sit in the cabinet next to the controller and verify at all times that the controller never generates an unsafe condition, meaning one where signals show green in two directions that would result in a vehicle or pedestrian injury. Peek Traffic manufactures and sells a couple different varieties of CMUs and MMUs.

			Double Diamond MMU – Peek's premiere NEMA malfunction monitor unit. Will operate with, and autorecognize, either TS1 or TS2 type compatibility cards. The large easily legible display shows the dynamic status of each input on each channel. Exceeds both NEMA TS1-1989 functional and environmental requirements for a conflict monitor and NEMA TS2-2003 functional and environmental requirements for an MMU. Records high and low voltage conditions - an industry first.
			2010ASP CMU – Dual processor based, the 2010ASP CMU accepts inputs from sixteen signal channels, each channel having three indicators, and can calculate the RMS voltage for each input. The 2010ASP stores log files of events for downloading and viewing on a personal computer using a front panel, 9-pin serial connector and Microsoft Windows® compatible software. Compatible with both 170 and 2070-Type controllers.
			2010ASP/NYC CMU – Designed to fit in the ASTC cabinets, the New York City version of the 2010ASP Conflict monitor unit works with Peek's ASTC and ATC traffic controllers. Otherwise, it is very similar to the 2010ASP CMU.

 

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