I know there is a resistor on wpc games that discharges the high power to ground when the door is opened or the machine is switched off but does this happen when you switch off a sys7 game. Or is the H/V still lurking.
Pinball info
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Voltage discharge on a Wms sys7
- Thread starter paddythegreek
- Start date
On a Williams machine, the switch/switches which operate when the door's opened aren't directly concerned with the display voltages. Pre Wpc, the switch connects directly to the 'Cpu' side of the board architecture, while with Wpc it's one location of the switch matrix. The 'Interlock' switch added to later Wpc games (during the wide-body era, AIR) breaks the transformer secondary circuits for solenoids and flashbulbs.
It'll be down to the design of the display power circuits whether 'bleed' resistors are used to drain away residual voltage after the machine is switched off. The early Bally system does, but I'm not sure about Williams. Try measuring one/both of the voltage rails while/after the machine's switched off - if the level hasn't dropped after 30 sec. to a minute then it doesn't, or it isn't working.
It'll be down to the design of the display power circuits whether 'bleed' resistors are used to drain away residual voltage after the machine is switched off. The early Bally system does, but I'm not sure about Williams. Try measuring one/both of the voltage rails while/after the machine's switched off - if the level hasn't dropped after 30 sec. to a minute then it doesn't, or it isn't working.
