American Flyer S gauge model 7 transformer problem

[impalaman]

I acquired a model 7 75watt AF transformer with a bad cord and installed a new one. It works perfect except the reset button won't cut current unless the short circuit bulb is removed. Whit it out, the button works fine. With the bulb screwed in, it won't change the current. The circuit breaker and everything else looks good to me. What can I be missing?

 

[impalaman]

UPDATE: On a hunch, I tested it under load and it worked like it should. Testing the first time I used an AC multimeter. Only thing is the red light comes on when pressing the reset button with throttle on. I'm guessing the Model 7 transformer is supposed to be like that. Am I correct?

 

[Bruette]

Am I correct?

I wish I knew.

 

[Dub]

The reset button kills the power by separating contacts. It does not take a lot of effort to do that. If you force it down it make another contact. Just a guess. All I have is a 7b and I am not sure of the difference. It is not very complicated so you could draw out the connections. A few pictures may help too. The 7 and 8 models are very much alike.

I did notice the 7 has four terminals and the higher variable voltage to run standard gage. This was eliminated on the 7B

Does it look like this????

 

[impalaman]

Thanks Dub. Yes, looks just like yours and has 4 terminals like you said. Does your red light come on when pressing the reset button and under load with the throttle on?

 

[Dub]

The bulb I have is 18 volts screw base. The power shuts off under load with no light.
I did notice the reset button untrips something when it trips. So untripped the power cuts off, and resets when the breaker is tripped. I suggest tripping the breaker and then reset it.

 

[impalaman]

The bulb I have is 18 volts screw base. The power shuts off under load with no light.
I did notice the reset button untrips something when it trips. So untripped the power cuts off, and resets when the breaker is tripped. I suggest tripping the breaker and then reset it.

Thank you. I've tried everything with the circuit breaker and think it's alright. Another interesting fact is when I had it apart testing, it was unplugged and with a continuity tester across the base post and the other track power terminal used for 7-15v, there was continuity with the throttle on and the reset button pushed down, and the bulb in place. When I take the bulb out, no continuity.

 

[Dub]

It should not do that. With the cover I see the disconnection of a set of points
It is only at the reset after power loss that something else is moved.
Here is the sketch of the 7B

 

[Dub]

I found the problem.
I removed the case and shorted the transformer and noticed the position of the circle piece on the left.
If you look above the bar is inserted into a step on the wheel. That is the set position of which you are not in. The bar if you look at yours extends beyond the step and rests on the outer circle. By pressing down harder the top bar rotates the wheel and forces the bottom bar back into the step, thereby resetting the transformer. When it was halfway, the light went on when the button was pressed. The light goes out when the bottom bar is corrected.

TRIPPED

RESET

 

[impalaman]

I found the problem.
I removed the case and shorted the transformer and noticed the position of the circle piece on the left.
If you look above the bar is inserted into a step on the wheel. That is the set position of which you are not in. The bar if you look at yours extends beyond the step and rests on the outer circle. By pressing down harder the top bar rotates the wheel and forces the bottom bar back into the step, thereby resetting the transformer. When it was halfway, the light went on when the button was pressed. The light goes out when the bottom bar is corrected.

TRIPPED



View attachment 214811

RESET

View attachment 214812

I see exactly what you're saying. Unfortunately my breaker is working well. It's always in the untripped position. I even set it off and it tripped like your first pic, then it reset after I pushed the reset button. But I'm still wondering if the red light is supposed to light up when using the reset button to change direction.

 

[Dub]

No it should not. The button should work easy and break the connection which is ideal for reversing the engine.
When tripped the center bar touches the top which I presume gives the red light.

All you can do is check the bar positions and check the wiring.

 

[impalaman]

No it should not. The button should work easy and break the connection which is ideal for reversing the engine.
When tripped the center bar touches the top which I presume gives the red light.

All you can do is check the bar positions and check the wiring.

Right. Thanks for everything. I'll go at it again.

 

[Dub]

The bulb could be a lower voltage.
There are screw adjustments but have no idea how.