Em pinball keeps blowing fuse

dyno

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My Super Straight Em pinball machine blows the playfield light fuse after playing for a bit. When it replace the fuse it works fine but it seems if the ball hit a few targets and a bumper the fuse will blow, also occassionally when playing the lights will go dim also. Is it in need of a new bridge rectifier?
 
Just asking, not meant to belittle here but are you sure its the correct type fuse?

I mean could you be using a fast blow fuse, when a slow blow should be used?
 
No worries, I would ask the same question about what fuse was used to replace the blown one. The original was a 15 amp slow blow fuse and that is what I used as a replacement, the pin was missing a bunch of bulbs on the back box and playfield which I replaced so I am thinking maybe the previous owner was having the same issue and removed some of the bulbs, but it is only the fuse for the playfield that blows and all the lights still work on the back box.
 
Fixing a Failed Lamp Fuse.
If the game is blowing a 6 volt lighting fuse, that is often caused by a shorted light bulb or light bulb socket. Or a wire for the GI (general illumination) is touching the metal frame of the game. This will of course blow a fuse, and these problems can often be hard to find.

Look under the playfield for a lamp socket that has the "tit" bent over accidentally and is touching the "base" of a lamp socket. This is common on lamp sockets on the edge of the playfield, because the playfield can be accidentally lower at a slight angle bending a lamp socket. Also if you took all the parts off the top of the playfield to clean it, check all the lamp sockets incase something metal fell inside a socket.

The easiest way to find a light short is to make a small "cheater" out of a small circuit breaker. Take a blown glass fuse, and solder the small circuit breaker to the ends of the fuse. Now insert the fuse into the game and turn it on. If there is a short, the breaker will 'blow' and can be reset. This makes finding the short in the GI circuit A LOT easier (and cheaper since you're not replacing the fuse a million times.

Now to find the short. I break the circuit down into "half". That is I cut the GI wires as they enter the playfield (in the case of a playfield short), and power on. If the fuse does not blow, I add 10% to the string and re-cut. Keep doing this until the short if found.

Also it's a good idea to do a visual inspection of each lamp socket. Remove all the light bulbs too (you were going to replace them all with new #47 bulbs anyway, right?) If the fuse stops blowing with all the bulbs removed, then there was a shorted bulb. Replace the bulbs one at a time with the game turned on to find the culprit (or just install new bulbs). Sometimes flashing #455 bulbs can short too. If the light fuse still blows with all the bulbs removed, there is either a shorted socket, or maybe a short at a connector (see the section below on connectors).

****this was copied word for word from http://marvin3m.com/em/index2.htm#low ****
 
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