Transformer Question- Harlem Globetrotters

I am in the process of swapping in a new bridge rectifier board for my Harlem Globetrotters. The first thing I did was read the instructions and compare the wiring chart to the way my game was wired.

The instructions say that transformer lug one should be a yellow 18 gauge wire and transformer lug 5 should be a red 18 gauge wire. My game has a red 18 gauge wire on lug one and a yellow 18 gauge wire on lug 9.

This led me to pulling up the wiring diagram. I saw in the wiring diagram table for the power line connections that lugs one and three should be strapped together and lug five should be strapped to lug seven for 120 volts. The table shows lug one should be strapped to lug 3 and lug 9 strap to lug 11 for 115 volts, which is how my game is currently configured.

The line voltage at my house is right at 120. Should I go ahead and change it over to what the chart says for 120 volts by strapping lug one to lug 3 and strap lug 5 to lug 7? It also says for 120 volts to apply power to terminals one and five. Mine currently has power to terminals 1 and 9. If it's recommended to switch it to the 120 volts configuration, would I just move the yellow wire over to lug 5?

I wonder if this could be the reason the bridge rectifier that powers the feature lights went out multiple times?

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#2 2 years ago

DAV

wayout440

Pinside member

Berea, OH

11y 113K 11,264 3 12

For 120VAC, move the heavy yellow wire over to lug 5 and jumper lug 5 to lug 7. Remove jumper between lugs 9 and 11. I doubt that would be causing your previous bridge failures for feature lamps, the bridge is usually rated for max 200VAC. The switched illumination lamp bridge AC input is expected to be roughly 7.8VAC from the transformer secondary output.

#3 2 years ago

AMR

BigAl56

Pinside+ Frequent

Palatine, IL

7y 64,800 1,655

If the transformer is optioned for 115v and your home is actually 120 you would do well to re-option the transformer. The low line configuration will boost the output a few volts which over time will result in lamp and other power fails.

#4 2 years ago

guitarded

Pinside member

OP
Quoted from pindude80:
I am in the process of swapping in a new bridge rectifier board for my Harlem Globetrotters. The first thing I did was read the instructions and compare the wiring chart to the way my game was wired.

Which replacement Rectifier Board are you installing?

#5 2 years ago

FUK

pindude80

Pinside member

Wayout and Big Al, thank you for the replies and info! I was thinking it would be best to set it up for 120 volts also but wanted to ask here first. The solenoids fire hard, the game plays very fast, is tough and frustrating, and I have been looking for a way to slow it down a bit so this might help.

Guitarded, I bought an assembled bridge rectifier board from Pinball Life. The brand they sell is Anarchy. I haven't installed it yet but everything seems very well built from looking at it.

#6 2 years ago

guitarded

Pinside member

OP
Quoted from pindude80:
Guitarded, I bought an assembled bridge rectifier board from Pinball Life. The brand they sell is Anarchy. I haven't installed it yet but everything seems very well built from looking at it.

Black Board, right?

I have been having issues with mine (actually have 2 here) and it is the same Bridge Rectifier (used by control lamp circuit) in both that has been at issue. Just thought I would ask and see if it was the same board that I put in my Skateball as I have been fighting with the controlled lamps in that one.

#7 2 years ago

FUK

pindude80

Pinside member

Quoted from guitarded:
Black Board, right?
I have been having issues with mine (actually have 2 here) and it is the same Bridge Rectifier (used by control lamp circuit) in both that has been at issue. Just thought I would ask and see if it was the same board that I put in my Skateball as I have been fighting with the controlled lamps in that one.

Yes, it's a black board. I'm getting ready to install and test it out after I reconfigure the transformer. I'll post my results.

#8 2 years ago

FUK

pindude80

Pinside member

I reconfigured the transformer for 120 volts. The game played fine and this seemed to maybe have calmed it down a little bit, which is what I was hoping and looking for.

I checked all of the test points on the new bridge rectifier board and test point one on the lightboard, everything was in spec. I played about five games and everything seemed to function as it should.

#9 2 years ago

guitarded

Pinside member

OP
Quoted from pindude80:
I checked all of the test points on the new bridge rectifier board and test point one on the lightboard, everything was in spec. I played about five games and everything seemed to function as it should.

Assuming this is after you replaced the blown rectifier on the board?

Awesome news.

#10 2 years ago

GPE

G-P-E

GPE

Omaha, NE

13y 76,800 2,778 4

Puzzled - I still cannot figure out why the bridge rectifier would have blown. The voltage would not have been tremendously higher (most common sizes are rated at 200 and 400V) and unlikely that the current draw would have been any different.

With the higher voltage, I can see why the lamps would burn out quicker but not why the bridge rectifier would burn up.

#11 2 years ago

guitarded

Pinside member

Quoted from G-P-E:
Puzzled - I still cannot figure out why the bridge rectifier would have blown.

I have two here that have blown the same rectifier.

Will be installing the repaired one this week as I was able to source a known working / original Transformer (and the one I was working with was an unknown replacement). It tested fine on the bench, but who knows what it is/was doing under load?

Will report beck once we get done.

#12 2 years ago

FUK

pindude80

Pinside member