Traffic Controller Frequently Asked Questions / FAQ

Illegal pre-emption device / MERT
Who? / Why?
Real life intersection
Unused outputs
LED Lights
Fluorescent bulbs
Multiple bulbs per output
COLD Temperature issues
Customized operation
PED walk/don't walk mode
Changing Caution-Mode / Flash Mode
Using 12-volt inverters
Light Dimmers
Driving Relays instead of bulbs

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Q>Is this one of those units that will let me change the light from RED to GREEN when I am approaching an intersection?
A>No, this is not one of those units.

Q> Who would want one of these?
A> This is a controller for people who own an old traffic signal and want it to operate like a real signal would for visual effect.  Some people then hang them in their garage, pool room, backyard, etc.    Some creative people have used them for Halloween and Christmas displays to trigger lights and small motors / animations.

Q> Can this board be used for actual traffic-flow control of a REAL intersection in place of an industrial controller?
A> No.  The SYNC series of boards are meant for "visual effect" use only, and are not for directing "real" traffic.

Q>  I have a standard three light signal, but may want to add a pedestrian walk/don't walk signal at a later time.  Can I use a 5-output  (SYNC-5) but only wire up the 3 outputs for the signal and leave the walk/don't walk outputs unused?
A> Yes you can.  Just wire up the outputs you need.  Leaving outputs open does not harm the board.

Q> Do these controllers work with LED type signal lights?
A> YES!  As long as the LED light is designed to accept 110 - 120 VAC, it will work fine.

Q> Can I use the low-wattage screw-in fluorescent bulbs?
A> The board will light them fine.  However, tests have indicated that "some" compact fluorescent bulbs have a shorter life-span when turn on and off frequently.

Q> Can I run two bulbs per output for a four sided traffic light?
A> Yes, you can run multiple bulbs per output, as long as the total wattage of the bulbs do not exceed 150 watts per output.  A common wattage for traffic light bulbs is between 35 and 40 watts, so two of these bulbs would be well below the wattage limit.

Q> I have a light hanging outside year round.  Would the electronics hold up to weather, such as cold temps below zero?
A>The enclosure for the board should be water proof. If rain / moisture seeps into the enclosure and onto the board, damage will result. The components are guaranteed to 0 deg. F. Technical Specs say -30 C to +105C.  Condensation will complicate things. A shroud of fiberglass insulation around the board would help in lower temperatures, as the triacs generate a small amount of heat that helps keep the board warm. A coat of conformal coating will help protect the board as well. Protect the time-set push button with masking tape when using conformal coating.

Side note about COLD TEMPERATURES and light bulbs with filaments
If the environment is VERY COLD, this can cause an unusually high surge current when a bulb is turned on from a cold start, as the filament resistance is very low until it heats up. This process happens in a fraction of a second. The higher the wattage of the bulb, the more pronounced the effect.  If the temperature is low enough, the filament may not be able to heat fast enough, causing an excessive current draw.  This can result in blowing the on-board fuse and possibly damage the triac that switches power to that bulb. The typical symptom of a damaged triac is that the bulb stays on continuously.

There are two possible solutions in cold-temperature situations:

#1> Resistors can be added from the NEUTRAL wire to each terminal output (R,Y,G) to allow just enough current to flow through each light to keep the filament warm, but
low enough so no light is visible.  This is also known as pre-heat or "pre-heating the light" (common in theatrical lighting). Something in the range of 2K to 4K at approx. 10 watts (one for each bulb/output)  should work, although you may have to experiment to find the ideal value for your setup.

#2> Another solution would be to put a resistor between each output and it's associated bulb (3 total, wired like a fuse), to "soften / cushion" such a surge. Three 10-ohm 25 watt resistors should work fine. Resistors are available at a local electronic store or you can find them on-line as well. . Resistors can get HOT, so take precautions in mounting them to avoid heat related damage. 

Q> I have an application for your board, but I need it to operate a little differently.  Can it be modified for other applications?
A> Yes... to a certain degree.  The wattage and voltage ratings cannot be changed.  However, the control-IC can be altered to do many things. 

Q> Does the 5-OUTPUT PED SYNC-5 Walk / Don't walk outputs flash like a "real" pedestrian signal?  How does it operate?
A>Yes.  There are 4 "steps" to the standard SYNC-5 cycle.  Each step can be from 1/2 sec to 25 minutes:
Step 1> Signal is GREEN, Green WALK in ON (solid)
Step 2> Signal is (still) GREEN, Green Walk turns off and RED D-WALK starts flashing
Step 3> Signal turns YELLOW and (at the same time) RED DON'T-WALK goes SOLID
Step 4> Signal turns RED (RED DON'T-WALK is still solid ON)
...repeat cycle

Q>How do you change the caution mode "mode"... i.e. flashing red,  flashing yellow,  etc.?
A>When caution-mode is initiated (by connecting the caution-mode input terminals together) pressing the time-set push button "STEPS" through the flashing modes. The current selected mode is always stored in non-volatile memory, so it remembers the mode when power is removed.

Q>Can I use a 12VDC Inverter to power the board from a 12 volt DC source?
Only inverters with  a sine-wave output that matches or exceeds the quality of standard 120 VAC residential power will work.
DO NOT USE Inverters labeled "modified sine wave".  These will destroy your controller.

Q>Can I use a dimmer switch to control power to the board to dim the lights?
A>No.  A dimmer changes the AC power in a way that will damage the traffic controller board. Use lower wattage bulbs to reduce the intensity as well as extend your controllers life.

Q>If I need to control/switch more wattage than the outputs are rated for, can the outputs drive relay coils instead of bulbs to allow the relays to switch a larger load?
A> Yes!  Just make sure the relay coil voltage is 120VAC and the contact rating of the relay meets or exceeds your lamp wattage/amperage switching requirements.  If you are not familiar with relays, you must consult with a qualified electrician to avoid damaging the controller.
xample of 15 Amp (resistive load), 120VAC coil relay and socket:
Relay: TYCO part# K10P-11A15-120 (Digikey part#PB321-ND)
Socket: TYCO part# 27E895 (Digikey part#PB332-ND)

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