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diagnosis after blown varistor ??
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gbe...@gmail.com
Jun 20, 2013, 9:01:18 PM6/20/13
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One of our games (EBD) has a clearly blown varistor (exploded by the looks of it) and I'm wondering about pursuing the cause. The game is still fully functional save for a new hum/buzz on the audio (sounds 60 Hz). There was no obvious antecedent 'event' that anyone here can remember but I don't remember seeing this the last time the pf was raised. So my question then is, where is the first place I should start looking. Transformer, caps, etc ?? Thanks guys...
barakandl
Jun 20, 2013, 10:17:56 PM6/20/13
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On Thursday, June 20, 2013 9:01:18 PM UTC-4, gbe...@gmail.com wrote:
> One of our games (EBD) has a clearly blown varistor (exploded by the looks of it) and I'm wondering about pursuing the cause. The game is still fully functional save for a new hum/buzz on the audio (sounds 60 Hz). There was no obvious antecedent 'event' that anyone here can remember but I don't remember seeing this the last time the pf was raised. So my question then is, where is the first place I should start looking. Transformer, caps, etc ?? Thanks guys...
Varistors short then go open on an over voltage. Can figure they fatigue over time. I would replace the component and not worry about it unless it goes again.
> One of our games (EBD) has a clearly blown varistor (exploded by the looks of it) and I'm wondering about pursuing the cause. The game is still fully functional save for a new hum/buzz on the audio (sounds 60 Hz). There was no obvious antecedent 'event' that anyone here can remember but I don't remember seeing this the last time the pf was raised. So my question then is, where is the first place I should start looking. Transformer, caps, etc ?? Thanks guys...
c...@provide.net
Jun 21, 2013, 6:19:45 AM6/21/13
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the end, they blaze up in smoke and glory and dead short, blowing the
game's line fuse and the main's circuit breaker/fuse too. of course if
they see over 130 volts (north america) that will make them direct short
too. that's what they do.
So i agree, just replace it (or temporarily just cut it out of the circuit).
Then before powering on for the first time, disconnect the J4 connector
from the MPU board (lower left corner), and power up. Check all the
voltages at the solenoid driver board. If OK, then re-attach MPU
connector J4 and proceed.
TheKorn
Jun 21, 2013, 5:26:05 PM6/21/13
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c...@provide.net wrote in
news:b89d4ba1-3d13-48a5...@googlegroups.com:
> I agree, varistors have a finite number of power on cycles. when you
> reach the end, they blaze up in smoke and glory and dead short,
> blowing the game's line fuse and the main's circuit breaker/fuse too.
> of course if they see over 130 volts (north america) that will make
> them direct short too. that's what they do.
>
> So i agree, just replace it (or temporarily just cut it out of the
> circuit). Then before powering on for the first time, disconnect the
> J4 connector from the MPU board (lower left corner), and power up.
> Check all the voltages at the solenoid driver board. If OK, then
> re-attach MPU connector J4 and proceed.
Another vote for the "no-diganosis" method. Keep in mind that the varistor is in
circuit even when the game is off, so if the game saw a large spike while off, the
game would be fine but the varistor toast. Though they are supposed to blow to a
short when that happens.
--
Have a home video that's trapped on your camera? Want to share it on the web or on
DVD?
http://www.webwidevideo.com/
news:b89d4ba1-3d13-48a5...@googlegroups.com:
> I agree, varistors have a finite number of power on cycles. when you
> reach the end, they blaze up in smoke and glory and dead short,
> blowing the game's line fuse and the main's circuit breaker/fuse too.
> of course if they see over 130 volts (north america) that will make
> them direct short too. that's what they do.
>
> So i agree, just replace it (or temporarily just cut it out of the
> circuit). Then before powering on for the first time, disconnect the
> J4 connector from the MPU board (lower left corner), and power up.
> Check all the voltages at the solenoid driver board. If OK, then
> re-attach MPU connector J4 and proceed.
circuit even when the game is off, so if the game saw a large spike while off, the
game would be fine but the varistor toast. Though they are supposed to blow to a
short when that happens.
--
Have a home video that's trapped on your camera? Want to share it on the web or on
DVD?
http://www.webwidevideo.com/
gbe...@gmail.com
Jun 21, 2013, 9:08:26 PM6/21/13
to
On Thursday, June 20, 2013 6:01:18 PM UTC-7, gbe...@gmail.com wrote:
> One of our games (EBD) has a clearly blown varistor (exploded by the looks of it) and I'm wondering about pursuing the cause. The game is still fully functional save for a new hum/buzz on the audio (sounds 60 Hz). There was no obvious antecedent 'event' that anyone here can remember but I don't remember seeing this the last time the pf was raised. So my question then is, where is the first place I should start looking. Transformer, caps, etc ?? Thanks guys...
Consensus then is to ignore/replace and monitor for any further difficulties. Sounds good here. Is there a recommendation for a varistor replacement ??
> One of our games (EBD) has a clearly blown varistor (exploded by the looks of it) and I'm wondering about pursuing the cause. The game is still fully functional save for a new hum/buzz on the audio (sounds 60 Hz). There was no obvious antecedent 'event' that anyone here can remember but I don't remember seeing this the last time the pf was raised. So my question then is, where is the first place I should start looking. Transformer, caps, etc ?? Thanks guys...
barakandl
Jun 22, 2013, 1:16:21 PM6/22/13
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barakandl
Jun 22, 2013, 1:18:00 PM6/22/13
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