A friend of mine ordered a ColorDMD for his TAF (excellent choice!). It connects to the unregulated 12V power supply via a passthrough connector to J116-117 or 118 on the driver board. I tested the unreg supply at TP1 and it's measuring about 17.5V which seems REALLY high to me. I don't want to risk frying this color DMD. Usually I would expect somewhere in the 13.7-14.2V range for unreg 12V.

I'm not sure that anything even uses that circuit (coin door), so the game plays perfectly otherwise.

Besides C30 and BR5, is there anything else I should check? What is the expected AC voltage coming into BR5?

Thanks in advance!

#2 7 years ago

GFY

Otaku

Inactive member

Unknown

9y 93,150 3,813

Seeing as you're not sure what uses that, you haven't disconnected the load to it anywhere, right?

#3 7 years ago

ESA

stangbat

KC Pins

13y 86,900 3,111 19

Check how the transformer is jumpered, make sure it isn't set up for low voltage (105v). Pic of the correct orientation is in this section:

http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#WPC_5VDC_Power_Derivation_Path

#4 7 years ago

---

ForceFlow

Pinside Moderator

9y 238K 31,362 268 14

Unregulated power will usually be a bit on the high side because...it's unregulated. It's usually just raw voltage off the transformer.

I'm not sure how ColorDMDs are supposed to be hooked up, but I would assume it would be best to connect it to *regulated* voltage. However, if the instructions say it's ok, there might be a regulator built into the ColorDMD.

#5 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

Yes, you are connecting it correctly to the Unregulated 12v. Randy once told me up to 18v is ok. The ColorDMD board does have an onboard regulator.

#6 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

Many machines I had measured 15.4v on the unregulated 12v.

#7 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

OP
Quoted from wxforecaster:
I'm not sure that anything even uses that circuit (coin door), so the game plays perfectly otherwise.

Cannon motor runs off it, I do believe.

#8 7 years ago

EMB

wxforecaster

Shoot Again Pinball Repa

11y 87,050 1,835

A canon motor on Addams Family. Interesting lol.

#9 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

Sorry, I was thinking T2 for some dumb reason. Maybe I should not had responded so late last night. haha

TAF has some optos and Thing motor.

#10 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

OP
Quoted from wxforecaster:
Besides C30 and BR5, is there anything else I should check? What is the expected AC voltage coming into BR5?

From Pinwiki. It does not give a voltage range of what could be considered good or bad.

LED7-TP1
Normally lit. AC voltage is rectified to about 12VDC by BR5 and smoothed by C30 to provide unregulated 12VDC power. This 12VDC power is shown as "+12V Power" on the schematics. It is used to power motors, optos, and other game features that do not require a precise 12VDC. This power is fused by F116.

#11 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

I do not see an issue with 17.5v using the ColorDMD. You are using the ground braid wire in the backbox as the ground reference?

#12 7 years ago

ESA

stangbat

KC Pins

13y 86,900 3,111 19

So, have you checked how the transformer is jumpered?

#13 7 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,629 104

Install that ColorDMD.

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