Q: no 24 volts at bell, meters, handle release, comes from i/o bd??

[pinballplus]

Hello, I have a s2000 that 24 volts is missing (orange wire) to the above items. The orange wire (24vdc) comes from  the I/O board which surprises me as I thought it would get the 24 V directly from the power supply directly with I/o bd supplying ground pulse. Not sure why this is. Anyways continuity is good as well as the I/o bd. If I jumper 24 v to the above items from the power supply directly they will work but not right as something is amiss and not sure how the 24 vdc is run through the I/o bd or where ti comes from (back plane bd?) Thanks ! JR

[rickhunter]

The 24 volts should come out of the power supply that is mounted in the back of the machine.  But if your flourescent lights work, you should have 24 volts working.  All those peripherals listed are senet devices.  Maybe you have a burnt trace in your motherboard?

[CommTech]

Hi JR,

The handle solenoid does not energize unless there is a credit in play.  The bell is a pulsed 25 volt, but only when a jackpot is hit.  The meters are also pulsed. 
What problem are you having that you are tracing the +25 volt line?

[pinballplus]

hello, thanks for the help. The above items have no 24vdc ever. it seems it (24vdc) comes from the I/o bd not directly from the power supply. If I jumper 24 vdc to the items directly they work. Just not sure I want to do that as it may cause issues down the road.  Thanks! JR  Also wondering term "senet device"s and meaning? as Im learning a lot about s2000 machines.

[foster]

SENET I believe stands for SEcure or SErial NETwork (makes sense to me)  but is not the only serial network in the machine the other one is called Netplex.

Are you checking the orange wire to chassis or black with red or orange stripe. do not assume any green wire in the machine is a ground wire unless it is attached to the chassis.

I know the solenoid has 2 orange wires one is the 25V the other one is the return to ground via a logic gate in the Cabinet I/O
The bell  and meters work the same way.
The ground wire in the meter harness is to ground an input back to the mpu, which keeps you from disconnecting the meters without installing a jumper plug or the like

[Retro tech repair]

meters are switched on the 24v side using a darlington array, i show jackpot going to the same darlington. but i see bell and handle release being switched on the gnd side by the same fet.

[CommTech]

hello, thanks for the help. The above items have no 24vdc ever. it seems it (24vdc) comes from the I/o bd not directly from the power supply. If I jumper 24 vdc to the items directly they work. Just not sure I want to do that as it may cause issues down the road.  Thanks! JR  Also wondering term "senet device"s and meaning? as Im learning a lot about s2000 machines.

If your plugs are seated correctly on the I/O board and you measure +25 volts at the plug going into the board, then It would appear you have a bad I/O board.  Simply bypassing the I/O board will not work.

 

[Retro tech repair]

Do not attempt to bypass the io board the ics that run the senet on the mpu will blow just from plaiting in a device while they are active let alone if you accidentally apply 25v to a data line.

[pinballplus]

I checked the orange wire 24 vdc going into the I/O bd and its not present . Following the wire the 24 vdc seems to come from the cpu bd directly at least for this circuit.  I was just surprised it was done this way. It seems a short on the 24v circuit (bell/handle coil)  would fry the cpu instead of a fuse. Thanks! JR

Like I mentioned If I splice the little thin orange wire and add the 24vdc it seems to work fine.

[Retro tech repair]

The darlingtons and fets used isolate the lower voltage circuit from the higher voltage circuit so it something goes wrong you usually just blow an io board.

[CommTech]

I checked the orange wire 24 vdc going into the I/O bd and its not present . Following the wire the 24 vdc seems to come from the cpu bd directly at least for this circuit.  I was just surprised it was done this way. It seems a short on the 24v circuit (bell/handle coil)  would fry the cpu instead of a fuse. Thanks! JR

Like I mentioned If I splice the little thin orange wire and add the 24vdc it seems to work fine.

OK, now I understand. You are missing the +25v at the input to the I/O board (which comes from the motherboard).  Like Rickhunter said, you probably have an open trace on your motherboard.
I don't see a problem with bypassing the power at that point.

[Retro tech repair]

If it's an enhanced board check for fuses first.

[foster]

meters are switched on the 24v side using a darlington array, i show jackpot going to the same darlington. but i see bell and handle release being switched on the gnd side by the same fet.

I don't think so the meters are actually switched or logic controlled on the negative side, which is the same as the bell and solenoid.
The meter board has 25V wired directly to each meter and the negative terminal of each meter on the board connected to its own pin/wire back to the i/o board.
This is per the meter schematic.
The specs for a ULN2004 say it has 7 open collectors tied to a common emitter which is tied to ground, with diode protection for inductive loads tied to common
Look at the actual gate schematic.

IGT controls the player button lamps or LED's the same way.

[Retro tech repair]

The specs for a ULN2004 say it has 7 open collectors tied to a common emitter which is tied to ground, with diode protection for inductive loads tied to common

that saying can be kind of confusing they are not tied directionally to ground but through a parasitic diode this id done to stop any inductive load created by the magnetic field from coils or relays collapsing damaging the ic.

pin 9 on the uln2004 is your common and on the lower cabinet io board it is tied directionally to 25v

[foster]

The 25V is supplied to the meter board by pin 7 according to the meter board schematic and the negative/ground of each meter is tied to a separate output pin on the ULN2004A
ULN2002/2003/2004 are known as common cathode devices and since the emitters are connected to ground per the single gate schematic and datasheet that makes all 7 emitters connected to ground.
Each meter negative/ground terminal is tied to a separate output pin which is the open collector.
When the first transistor base is biased by a TTL/CMOS logic 1 (+6-15V for a ULN2004) both transistors turn on or conduct for that gate allowing current to flow through the pair of collector/emitter junctions.


This is not the first time I have dealt with ULN2003/4 devices. the S+ display has 2 ULN2003 to control the common cathode pins for 7-segment displays.
Since the LED's in are not inductive loads the common pin is Not Connected (NC). The segment anodes are controlled by a 4511 BCD to 7 segment decoder.

[Retro tech repair]

ok i see how that works now.

still for the op there are 2 15 amp fuses on the motherboard of enhanced boards if yours is enhanced check those. im not sure what they are for.

[foster]

They are for the 13, 25 voltage rails to the mpu and any devices that get power from the harnesses connected to the motherboard.

The 50x motherboard  does not have them and is prone to damage from overloads, shorts,or reversed polarity to a device.

[pinballplus]

      This is a great group!! You have all been a great help over the years. I was worried when the old site didnt work!! Just signed on again!




Thanks for all the help! Ive used the s2000's for events since 2010. They have been modified to award a prize upon a win. When the jackbot bell rings the 24vdc runs a vend motor via relay that vends a prize to the player. Ive always just used the bell harness to run the motor and relay. Ive always assumed the power comes from the power supply directly.  Im not too fond of the idea of the 24vdc being run through the cpu in case of a fault with the motor. Never had an issue and I believe i shorted something out in my work to come up with this issue. Im glad I did so I can know the games better:)

   Am I safe to run the 24 volts directly to my motor from the power supply? That way in the future if a fault develops with the vend motor(bell circuit) it wont burn open a 24v trace on the cpu. The ground signal would still come from the I/O board when the jackbot bell rings. 
   The board I have seems to be a non enhanced bd. Must be an open trace in the middle of the bd as I can not find it. Thanks in advance for your help!! JR

[CommTech]

      This is a great group!! You have all been a great help over the years. I was worried when the old site didnt work!! Just signed on again!




Thanks for all the help! Ive used the s2000's for events since 2010. They have been modified to award a prize upon a win. When the jackbot bell rings the 24vdc runs a vend motor via relay that vends a prize to the player. Ive always just used the bell harness to run the motor and relay. Ive always assumed the power comes from the power supply directly.  Im not too fond of the idea of the 24vdc being run through the cpu in case of a fault with the motor. Never had an issue and I believe i shorted something out in my work to come up with this issue. Im glad I did so I can know the games better:)

   Am I safe to run the 24 volts directly to my motor from the power supply? That way in the future if a fault develops with the vend motor(bell circuit) it wont burn open a 24v trace on the cpu. The ground signal would still come from the I/O board when the jackbot bell rings. 
   The board I have seems to be a non enhanced bd. Must be an open trace in the middle of the bd as I can not find it. Thanks in advance for your help!! JR

Unless the vendor motor is very low current, I would recommend a separate power supply for the vendor motor.  Plus, if anything should happen to the motor you will not have to worry about your slot machine power supply.