Appendix A: Model Specifications

The following table includes specifications for various models of portable changeable message signs. The table was created and modified from (MnDOT 2005).

Type C Portable Changeable Message Signs
Manufacturer ADDCO American Signal Daktronics Precision Solar Controls, Inc. Solar Technology, Inc. Ver–Mac Ver–Mac Wanco
Panel Dimensions 134" x 69" 137.5" x 79" 133" x 77" 127.25" x 76" 126" x 76" 133"x 71" 133" x 83" 130" x 72"
Type of Programming Device Handheld with LCD Readout Handheld with LDC Readout Standard keyboard with LCD Readout Specialized Computer Specialized Computer Standard keyboard with LCD readout. Handheld optional. Standard keyboard with LCD readout. Handheld optional. Standard keyboard with LCD readout
Lighted Programming Console LCD Readout is lit Lit LCD readout LDC Display is lit Backlit keyboard and LCD Window Backlit keyboard and LCD window. Waterproof LCD Readout is lit. LCD Readout is lit. Yes
Ease of Programming12 Easy to use quick programming Difficult. Too many steps to do a quick message. Must create message and then sequence. Difficult. We lacked access to all but the basic functions. Very Easy. Just follow the prompts on the screen. Easy once you understand the quick programming feature. Somewhat difficult to get rid of additional phases in a sequenced message. Somewhat difficult to get rid of additional phases in a sequenced message. Very Easy. All instructions for a quick sign are printed alongside the readout.
Ease of Setup Including Sighting13 Good – May be aimed from the ground Different. Requires the use of a wrench to lock and unlock the rotation feature. Must fully raise display before locking rotation. Requires climbing on unit. Easy. Can stay on ground throughout process. Rotation and solar panel deployment are electrically actuated. Solar panels deployed very slowly. Good. Sighting tube was misaligned. Can be aligned from the ground. Good. Can be aimed from the ground. Good. Used a compression ring to lock rotation. May be aimed from the ground. Good. Uses a compression ring to lock rotation. May be aimed from the ground. Good. Nice disk brake rotation lock.  Can be sighted from ground.
Angularity Distance (ft) 125' 100' 75' 100' 50' 150' 100' 75'

Trailer Information
Tire Size F78–15 ST 205/75–15 205/75–15 P235 – R15 225/75 R15 F78 – 15 205/75–15 205/75–15
Radial? No No Yes Yes Yes Yes Yes No
Welded Construction? Yes Yes Yes Yes Yes Yes Yes Yes
Advertised Windload 80 MPH 104 MPH Wind gusts 80 MPH N/A N/A N/A N/A 98 MPH with outriggers
Battery Description 12 volt system. 8–6 Colt Trojan T–105 12 volt system. 12–6 volt deka promaster 12 volt system. 8–6 volt. 12 volt system. 4–12 volt continental 12 volt system. 8–6 volt crown model CR–225 12volt system. 12–6 volt pow R Surge 12 Volt System. 12 – 6 Volt Interstate U2200 12 Volt system. 8–6 volt Exide GC 135
Solar Array Wattage 320 Watt. 4–8W. Shell 369 Watt. 3–123W Sharp 220 Watts. 2 – 110W. GE 225 Watt. 3–75W. Shell 450W – 80Watt 165 Watt. 3–53W. Mitsubishi 220 Watt. 2 – 110W Mitsubishi 240 Watt. 2–120W Kyocera
Steppable Fenders Yes Yes Yes Yes Yes Yes Yes No
Weight 2830 lb. 3000 lb. 2950 lb. 3540 lb. 2690 lb. 3600 lb. 3800 lb. 2640 lb.
Comments: Surge brakes. Electric brake option. Cable to display held up with spring. Solar array is tiltable and can be rotated independent from display.  Gull–wing design plastic covers for batteries and controls. Snow was able to get inside Surge brakes. Have to make sure there is a wrench of the proper size before venturing out to deploy device Surge brakes. Solar panels may be tilted. Programming unit was dead on arrival, which required replacing a circuit board.  I don’t know if the display was on auto–brightness or not. It seemed dim. Surge brakes, all metal construction.  Computer is at a good height for working on.  Raised and lowered slowly. Too thick hydraulic fluid? Surge brakes. Pintle or 2" ball hitch available.  Plastic battery and controller boxes.  Not easy to open clips.  Locking pins for storing computer can catch fingers or gloves.  Computer is at a good height for working on.  Display glare screen seemed to diminish LED intensity. Surge brakes. Electric brakes are an option.  Old style trailer. No hold down latch for battery box lids. Bungee cord attached to display cable.  Cable can drag. Surge brakes. Electric brakes are an option. Plastic boxes for batteries. Trailer was well balanced.  Tongue could be lifted by hand. No brakes needed with light weight. Outriggers offered as an option.  Needed because of light weight? Cable to display good. Only unit to have tongue wheel with screw jack. Raised edge around each character module prevents light bleeding in to next character.  Trailer is well balanced.

12 The values in these rows are subjective opinions of the MnDOT PCMS Evaluation team. These opinions are neither factually checked nor endorsed by the authors of the paper. The opinion values are included to increase the reader’s understanding of features of each PCMS model. [ Return to note 12. ]

13 Ibid. [ Return to note 13. ]

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