Scope

Site Considerations

Pre-construction

Determine the transducer location first. This is the center of the site. The center of the transducer must be located between two ties. This allows for the transducer claw to clamp under the rail.
Mark the tower locations. Tower Foundations should be directly out from the transducer 11 feet 6 inches from center of track.

Areas to Avoid

Comet Electronics recommends that the following site areas are avoided. Use this list as a guide only. Since all installations are unique in some manner, avoiding these areas is not always possible. A survey of each site should be done to determine preferred equipment locations, conduit runs, and antenna configuration based upon the particular application. The user and the system integrator must ensure correct and accurate system operation in the event the areas described below cannot be avoided.

Large metallic objects and obstructions in close proximity to the reading area
Areas where reverse train movements occur
Areas where train switching moves occur
Areas where “building” moves occur (dropping and adding cars)
Areas where train stoppage in front of reader systems is likely to occur
Areas with severe or multiple curves in the track
Switches
Track joints

Before digging, contact a qualified utility locator service. Utilities need to be marked before digging to safely avoid them.

See below a non-comprehensive list of utility locator services. Local authorities may need to be notified before work begins.

Service Provider	Locality	Contact
Call 811	United States	Call 811 or visit https://call811.com/
Click Before You Dig	Canada	Visit https://www.clickbeforeyoudig.com/

Comet Industries is not affiliated with or endorsed by any of the service providers listed.

Earthwork

Two Tower Foundations and a 3" conduits need to be installed below grade. All trenching must be at least 36" below top of rail.

Tower foundation holes

Minimum size 24" x 24" centered 11 feet from center of rail.
Hole must be deep enough to set the foundations at top of rail.

Trenching

All trenching must be at least 36" below top of rail.
One conduit trench is needed between the two foundation holes running through their center.

Tower Foundations

Install house foundation legs at top of tie level. All trenching is to be 36" below top of tie. Set tower foundations.

Recommended: 200lbs of Sakrete for the nearside.

Conduit

Install all conduits in the same trench. Lay conduit out, make the necessary cuts, glue cut pieces together as necessary, and bury the conduit.

Conduit runs on drawings are guidelines. They may be changed to fit site specific requirements. Use sweeps, not elbows!

Towers

Install tower sections and tower caps. There are holes present at the bottom of the tower. Use these holes to guide drilling through the foundation, and secure tower to foundation using provided bolts. Secure towers with six bolts each, for twelve total bolts.

Ground Rods

Install ground rods and cabling. (Pigtail at corner ground rods into hut.)

Use the CADWELD exothermic welding system for ground cable to grounding rod connections.

Junction Box and AEI Box

On the side of the nearside tower that the AEI box will be installed on, place the AEI box on top of the 4x4 spacers. While the box is supported, slide the tower clamps into the unistrut located on the back of the box. The clamps should be bolted to the tower securely once they have been slid into place.

The Junction box can be installed in the same fashion on the farside.

Heliax

Start installing the Heliax cable on the farside, pushing it to the nearside. When cutting the Heliax, leave enough to pull 4.5" into both the AEI box and the Junction box.

Refer to manufacturerʹs documentation for connector and wiring installation procedures.

Antennas

Place the center of the antenna 3 feet 6 inches above the top of the rail and 11 feet 6 inches away from the center of the rail. The tower face should be 12 feet from the center of the rail.

Place the second antenna directly across from the first.

Refer to Appendix C: Site Drawings for detailed installation drawings.

Wiring Power to the AEI Box

Power must be wired into the AEI box by a licensed electrician.

Wheel Sensor

Refer to Frauscher Wheel Detector Installation and Optimization for instruction on installing the wheel sensor.

Presense Subsystem

Refer to Presense Detector Installation and Loop Detector Pin Connections for instruction on installing the presense subsystem.

Batteries

An area inside each NEMA enclosure has been marked for battery placement. Install the batteries in the marked area.

Cell Antenna

Install the cell antenna above the AEI box.