TEO Signal Committee Meeting Minutes Meeting Date: 02/09/06 Waters Edge Conference Rm A Meeting Time: 9:00am - Noon Meeting Attendees: Roger Sowder Sue Zarling Kile Holm Al Espinoza Marlin Reinardy John Bieniek Ben Osemenam Jerry Kotzenmacher Steve Misgen Ed Andrajack Tom Dumont Cindy Gross Kevin Millage Brad Bruegger John Hoivik Jim Deans Pete Skweres Shongtao Dai Tim Bangsund John Tackman Old Business Battery Backup: Cabinets are at ESS for review and approval. Since we will likely have different vendors supplying the cabinets, cabinets will not look exactly the same. This is not an issue as long as the footprint is the same. Cost estimates for individual components of the service cabinet are as follows: $1200 for inverter $600 for (4) batteries $2200 per cabinet These cost estimates must be multiplied by 40% (overhead costs) for a total estimate of around $6000 per cabinet for a full battery backup system. At this time, there is no approved product for the inverter. The inverter must have at least an 1100 watt output. The batteries will be maintained and replaced at the districts cost. The cost could likely be passed on to the local agency through the agreement process. When replacing batteries, all batteries must be replaced at the same time. Replacing only one battery can cause an unequal drain/load on the four battery system, causing premature failure in all batteries. Mouse Prevention Update: Installations have been done in the field. No major issues other than the PA85 bases are hexagon shaped, leaving gaps at the corners. Caulk or putty may be used to close this gap. Pea rock at the bottom of the base has also been used with success. 4 cuts seem to work for the majority of the installations. Grounding of the wire mesh was discussed and should be done in the field. A ground nut is installed by the manufacturer inside the base. This can be used for grounding the mesh. Dialight Update: No problems to date. This subject will be removed form Old Business. OTSO will work on updating new products list. New position in OTSO will be working on the list for updates and will update the web site info.
LED EVP Indicator Light: Metro will try a new LED EVP light at 30 intersections, with a priority on rail road interconnected crossings. The new light is made by TCP (Technical Consumer Products, Inc.) Model number LR30AMB/WH27K. They come with a two year warranty. They cost around $100 per bulb. Loop Splice/Uraseal Splice Kit Shop testing proved that when installed correctly, the splice kit worked well. There was issue about the labor intense splice and the conditions required to do the splice properly. Will contractors take the time and care needed to do the splice effectively? Cost of the kit was comparable to the 3M spice we now use. The 3M splice is the only splice kit approved at this time. The shelf life of the kit is only 12 months. Metro will try a few test sites. Keep on old business. Poly heads - Metro plans to experiment with 30 new signals for polycarbonate heads. Dakota County has extensive experience with the heads. Metro will likely go with recommendations from the county. It was recommended to use the Frey 11-F bracket for the mounting of a 5-section head. C.O. will review other Poly heads and get any recommendations from the NCITE Signals Committee. Look for future updates on this product in old business. New Business Signal Training OSTO has class dates set for Signals 101 (March 23 rd ) and Signal Design (March 1-3). Roadway Lighting (May 23-24) will also be offered in 2006. Registration information is on the OTSO web site. The Advanced Traffic Controller is not scheduled at this time but will likely be offered in June of 2006. Mn/DOT Signal operators will have priority registration for this class. Signal Timing and Coordination will not be offered this year but will be in 2007. If there is a lack of interest in any of the class offerings, classes could be switched for another. It was also requested to have a cabinet training class, similar to the ESS training in the past, only more structured. OTSO will look into this. Cell Library The new signal cell libraries for Microstation are now in place. The change of the library from "Signal04.cell" will be automatic and will show up on your network design computers. The cells will now be separated into three categories. The layout, wiring diagram and charts. The three cell libraries will be named "siglay", "sigwire" and "sigchart". The new libraries will have all the old cells from signal04.cell and a few new cells such as the EVP light. You should not notice any other change in the cells other than the library location. All the signal cells have been approved by the CADD standards group. Any new cells to be placed in the three libraries must also be approved by the CADD standards group. Audible Peds In the near future, MN/DOT may be required by law to place audible pedestrian buttons and indications at all traffic signals. This will require buttons and indications in strategic locations. The source of the audible ped must be at a location that can lead a visually impaired person to the pedestrian ramp.
MN/DOT has a couple of intersections that have audible peds. In one location, the audible ped counts down the amount of time left for the don t walk ped clearance. Another example was to call the street name of the crossing that was green, Elm Street is now green. The audible peds were only installed for the crossing the visually impaired ped needed, not all four crossings. The cost of the button and installation is around $1500 per button. Terminal block/connector A new type Deutsch 2, 4 and 6 pin connector was presented to the committee. The connector is proposed to replace the terminal block connector in the transformer base. This replacement was being proposed due to the frequent number of failures with our current terminal block. It was debated whether the failures were due to the terminal block itself or an installation failure. The connector is currently being used by the RTMC with great success. Issues and changes that would be required to accommodate this type connector: The connector is UL approved for #14 wire and not approved for #12. Our current wire size standard is a #12 wire. Spec book would need to change. This is not an issue for the N.E.C. but pulling strength of a #14 to #12 has been an issue in the past. The connector could be UL approved for #12 in the future. The connector only comes in 2, 4 and 6 pin configurations. Wiring color codes and cables will change. Manufactures and vendors would need to stock cable specific only for this type of cable connector. No other city or county uses this connector for their signals; therefore, the cable would be specific for only MN/DOT. Color codes on this cable will need to change to meet our specific needs. The signal wiring diagram will change. Due to the above mentioned cable changes, the wiring diagram appearance will change. A detail on the connector will need to included within plans. Color conductor code chart will need to be modified. Connector is an environmentally sealed plug and may likely withstand any element encountered in a traffic signal base but has not been time tested in a traffic signal transformer base. Sole source Installation - The connector would require a special tool. None of the above issues or changes is significant enough to not evaluate test sites or use widespread if the connector proves to be worthy and practical. Metro has a test site at TH 36 at Hamline. Metro will also try additional test sites and report back findings. Subject will be placed as old business in future meetings. Things to consider for widespread use, before time tested evaluation TMC success with the connector was expressed. The TMC pedestal pole may not be an equal comparison considering the differences between a ramp meter and traffic signal. A contributing factor in the terminal block failure is the amount of moisture within the traffic signal pole. TMC pedestal poles are likely to have less condensation inside the pole. The failure consequences of the two systems are also different; therefore the failures at a ramp meter (if any) may go un-noticed for long durations. Frequency of failures at ramp meters may also be less noticeable when compared to a traffic signal and its fail safe components. Website brochure for the connector: http://www.deutschipd.com/dt_series_brochure.pdf
DC Voltage for Traffic Signals The question was asked if DC voltage could be used to replace our current AC 120 volt system. The committee expressed no distinct advantage or benefit of pursuing a DC voltage signal. Our current 120 volt components such as the controller are unlikely to have a DC alternative. EVP Vehicle list It was questioned if we need our current language in our agreements. The language states that the city will provide MN/DOT with a list of vehicles that have an EVP emitter. No districts currently keep or request a list from cities with this equipment. Districts may want this list in the future. Will remain in the agreement. Detectors placed on bridge For new roadways where a bridge and a traffic signal are being constructed at the same time; and when detector placement falls within a bridge deck, the signal project manager should work with MN/DOTs bridge office. The preferred method for both the bridge office and traffic is to place the loops within the deck, as it is poured. There should then be a splice box under the bridge deck for easy access. Considerations for the splice box location are over river crossings or over a roadway lane. The bridge office will recommend splice and hand hole boxes for the bridge. On existing bridges, loops have been mounted under the deck with success. Locating the loop in the proper place can be a challenge if bridge girder spacing is tight or limits proper location. EVP Light When there is a concurrent opposing phase with no left turn phase, should the EVP light flash for the phase that is not receiving the call? Current operation throughout the state is the light will stay steady. The committee agreed this was the appropriate operation. Microwave detection Operational issues for microwave detection were expressed. There may be concerns of the re-use of microwave detection systems from one temporary system to another temporary system. The detectors may have a limited life and may not be suitable for ongoing multiple signal projects from one year to the next. If problems occur on new microwave detectors, districts should work with the vendor or manufactures to resolve the problem. Video detection has been used on temporary signal with success, but the cost is considerably higher than microwave. Tomar EVP Metro had problems with the operation of this product that was attributed to a high power line. Be aware of this issue if you should have problems. Rail Road Preemption New signals being installed where RR preemption is required should now have gate down logic and a supervisory circuit, for one gate approaches. This is in addition to the advanced preemption call. Quad gate crossings will require additional vehicle detection, outside of the traffic signal system detection. When Rail road preemption is required, the district should work with Mn/DOTs Office of Commercial Freight and Railroads. All areas of the state have a designated railroad project manager. The traffic signal project manager will work with the railroad project manager. The railroad project manager will then work with the private rail companies to
assure the needs of the traffic signal are met. OTSO will outline our current practice in an official letter or tech bulletin. Grounding - with the use of NMC, grounding and the ground wire (1-1/c#6 stranded) has been an issue. In the past, we had 2-1/c #6 wires from the service cabinet to the signal cabinet. We require the same 2-1/c#6 wires and now also include an additional 1/c #6 stranded, terminated at both the service cabinet and signal cabinet equipment ground block. When terminating the #6 stranded ground wire at the pole base, attach this wire to the grounding nut within the transformer base. Also attached to this grounding nut will be the #6 solid bonding wire that will attached (by ground bushings) to the ground rod. A 1 conduit stub out along with a 5/8 x 15 ground rod will now need to be included in the pole notes. The grounding nut within the transformer base may have up to 3 - #6 wires attached to it, if the #6 stranded ground is extended (daisy chained) to another pole. The #6 stranded system ground wire needs to be terminated in the signal cabinet, not the service cabinet. As a rule, any electrical run with 120 volts shall have the #6 ground wire. It was also suggested to ground the mouse wire to the ground nut inside the transformer base instead of a self tapping screw to the base. The sample plan layout and wiring diagram on the OTSO web site http://www.dot.state.mn.us/trafficeng/standards/signalplansheets.html has been updated to reflect these changes. Use it as your reference for future signal plans. Round Robin Roger has suggested using aluminum poles for pedestal pole knockdowns. Cost of the aluminum pole is $170 compared to $110 for the standard steal pole. The added cost will be covered by the added life of the aluminum pole after a knockdown, which is estimated to be 3 to 1 over the steal. Ben will check if the aluminum pole has any issues such as being crash worthy. Next Meeting Wednesday, May 17th, 2006 9:00am 12:00noon Waters Edge Conference Room 176 Send agenda items to Jerry Kotzenmacher