SignalTraffic Forums

by **steven1981** on Fri Sep 13, 2013 10:01 pm

A couple of days ago, I discovered one of the glass fuses in my G.T.E. e/m signal controller dead (after the signal controller and signals wired to it were powered for a couple of hours).

It controls the actual dial timer itself, so, naturally, the dial timer stopped on an interval. I replaced the dead glass fuse with a new one of the same kind, and I used the appropriate number of amps (3 amps). Everything worked swell for less than a minute, then, once again, after a certain interval was activated on the dial timer, the fuse blew.

I only have two pedestrian signals wired to the signal controller (Marbelite LPS-20 and Winko-Matic L.E.D.), so not much is drawn I presume.

I'm thinking the problem may lie elsewhere within the signal controller, but I cannot be sure. Any thoughts?

by **notMUTCDcompliant** on Fri Sep 13, 2013 10:12 pm

Dial motor died right? sounds like the motor is getting tired, overheating, and blowing the fuse

by **steven1981** on Fri Sep 13, 2013 10:19 pm

notMUTCDcompliant wrote:Dial motor died right? sounds like the motor is getting tired, overheating, and blowing the fuse

When I place a new glass fuse in the slot and power everything up, the dial timer (including its motor) begins to operate properly again. I would assume that, if that is the problem, then the actual dial wouldn't rotate at all (even if a new fuse is installed). Correct?

I do have plenty of spare synchronous motors, so maybe I'll consider to replace the current one with another one. See if that makes a difference.

by **notMUTCDcompliant** on Fri Sep 13, 2013 10:27 pm

As things get older, slower, and bearings begin to get worn, more stress is placed on the motor, causing a higher amperage draw, causing more hear, causing an even higher amperage draw.

I would suggest putting the run/stop switch in stop, replace the fuse, and power it back up and see if it does it again. If not, then the motor or motor wiring is the issue.

by **steven1981** on Fri Sep 13, 2013 10:39 pm

notMUTCDcompliant wrote:As things get older, slower, and bearings begin to get worn, more stress is placed on the motor, causing a higher amperage draw, causing more hear, causing an even higher amperage draw.

I would suggest putting the run/stop switch in stop, replace the fuse, and power it back up and see if it does it again. If not, then the motor or motor wiring is the issue.

Yes, that is understandable, due to the kind of signal controller. I really did not think about that until you mentioned it in your comment above.

The signal controller itself is fairly new (maybe between 12 to 14 years old). The motor itself has a date on it, including the others that I have. I would presume that it indicates date of installment. "4-08" is marked on the back of the cover for the motor, so, if my assumption is correct, then it was in use for quite some time before everything was removed off the street about a year ago.

I'll take heed to your advice and see what happens. I really do not believe that there could be something wrong with the wiring behind the panel itself, since everything is fully intact. Nothing loose from what I see as I am typing at the moment.

I might be thinking a little too hard about the problem, since there's perhaps a simple cause.

by **TacomaJoe** on Sat Sep 14, 2013 12:24 am

Does the dial motor stop at a particular key. With our Eagle EF20s if one is wired as a master it will blow the fuse when the r1 (sync) key comes around. If the problem is repeatable, you can probably chase down a panel wiring issue. If one of the indications has a short, the fuse will blow when that interval comes around.

by **steven1981** on Sat Sep 14, 2013 11:47 am

TacomaJoe wrote:Does the dial motor stop at a particular key. With our Eagle EF20s if one is wired as a master it will blow the fuse when the r1 (sync) key comes around. If the problem is repeatable, you can probably chase down a panel wiring issue. If one of the indications has a short, the fuse will blow when that interval comes around.

I do tend to notice that the dial timer stops just right before the end of the amber interval for phase 1; however, this has not happened at this particular interval every time the fuse failed.

The beginning of the amber interval for phase 1 is when the sync key (green) comes in contact with the switch above it. In the signal controller, there is a special fuse for the green key, which is labeled as 1 amp. Though that fuse is still fine. I guess I could say at this time that there is nothing wrong with the sync feature.

Although, as I mentioned in my original post here, I have only two signals wired to the signal controller. Two pedestrian signals. One for each phase, so I do not have any traffic signals wired at all. I am not sure if one of them is having an effect on the operation of the controller.

Maybe I'll take a closer look at the signal wiring to see if there is an issue.

by **TacomaJoe** on Sat Sep 14, 2013 1:09 pm

I don't think signal wiring is the issue. A simple test would be to manual the cam through all the intervals and check the signals. The fuse for the sync may be on the wrong side of the short. You may try replacing the 3A fuse with a 150W lamp. Then rather than blowing a fuse, the lamp will light up.

by **vaughnsimon** on Sat Sep 14, 2013 1:14 pm

steven1981 wrote:Maybe I'll take a closer look at the signal wiring to see if there is an issue.

That sounds like a good plan! I Doubt if the dial motor is your problem. If the motor were drawing three amps, it would get hot to the touch pretty quickly.

If you can't find a problem in your signal wiring, try disconnecting them entirely to see if your fuses suddenly stop blowing.

Fuses can get expensive soooo......

If you do decide that your short is in the controller/backboard, my old trick was to remove all lamp loads, and then substitute a 150-watt minimum test lamp for the fuse. (I use a pigtail lamp socket with insulated alligator clips.) That will allow a maximum of one amp to flow. The dial motor should still run, and the lamp should glow a bit when the cam motor energizes. If you have a dead short, the lamp will light full brightness, and your timer will stop. At that point, use an insulated tool to probe around for the trouble. (Open up each signal contact in turn, flip switches, operate relays, unplug the dial, and use your Mark I eyeball until you find the trouble.)

by **steven1981** on Sat Sep 14, 2013 2:31 pm

I removed some unnecessary cam fingers, in which I originally used when I had traffic signals wired to the signal controller. As a result, everything is working smoothly as I am typing.

Though I do not want to waste another good glass fuse, the problem perhaps lingered amongst those unnecessary cams that were attached. The wiring below each signal circuit is fine, and nothing is loose. Though two cam fingers were rather loose, and they had a tendency to slightly move (when the cams and shaft moved) at a certain interval on the dial timer (red clearance before second phase), since a small barrier between each one is missing. Each section for a cam and finger has this barrier, but not for G1 and R2. When traffic signals were attached to it, I did encounter some minor flickers. That's about it. The dial timer sometimes stopped at the red clearance, which was when the fuse failed.

I'll leave the signal controller on for about an hour, and I'll see how everything goes. I don't want to necessarily say those unnecessary cam fingers and broken barrier in between G1 and R2 are the issue.

SignalTraffic Forums

Bad circuit?

Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Re: Bad circuit?

Who is online