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To the Honorable 'Mayor and City Council <br /> From the City Manager <br /> <br />May 6, 2002 <br /> <br />Subject <br />Installation of Twenty-four (24) Traffic Signal Battery Back-up Power Supply Units <br /> <br />Recommendation <br />By Motion, approve the purchase and installation of Twenty-four (24) back-up power <br />supply units for traffic signal controllers from Republic Electric, of Novato, California. <br /> <br />Background <br />Traffic control safety is affected by unpredictable power outages that cause the failure of <br />traffic signals. During power outages, there is a time lapse for staff to respond to set up <br />and remove four-way stop signs at affected intersections. Often Police officers must fill in <br />as temporary traffic control which affects police staffing. The installation of back-up power <br />supplies will provide supplemental power to the traffic signal cabinets during power <br />failures, resulting in continuous traffic signal operation. <br /> <br />The battery back-up is activated automatically similar to an uninterrupted power supply <br />generator. The unit has its own cabinet as space is too limited in existing traffic signal <br />controller cabinets to include the battery packs (see attachment 1 photos). <br /> <br />The back-up power supply will provide full intersection operation for up to two hours and <br />four-way red flash operation from three to 17 hours depending upon the overall <br />intersection load. Staff research indicates that the typical intersection will be powered for <br />at least five hours in red flash mode. This should provide adequate interim traffic control to <br />allow staff to respond and reduce the need for police officer presence at intersections <br />during power outages. This back-up power supply coverage will address safety and <br />operational concerns raised by unpredictable power failures as the result of weather and <br />other incidents. <br /> <br />This is the second phase of battery back-up purchases. Staff purchased the first eight <br />units in FY 99-00. The quality and reliability of the battery back-up systems has improved <br />since the initial purchase. This second phase will include the purchase of twenty-four <br />systems to be placed at twenty-four high volume intersections. The third phase will include <br />the five battery back-up units to be installed in five new cabinets as part of the RTSOP II <br />traffic signal controller renovation project. <br /> <br /> After this purchase and RTSOP II, 37 of 58 signalized intersections will have battery back- <br /> up units. The final phase will be requested in the future to complete the remaining 21 <br /> intersections. Additionally, Engineering has revised the traffic signal cabinet specifications <br /> to include a battery back-up system for all new intersections. <br /> <br /> Staff received three bids for the supply of battery back-up units as follows: <br /> <br /> Dimensions Unlimited, Inc. PBM 1250 back-up unit. $2,800.00 each <br /> Page 1 of 2 <br /> <br /> <br />