Sensitive to static
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Posts: 46,084
Hello
I have build a simple circuit using S2 and it works beautifully,
handling two motors, a relay and the input of 3 switches. However, in
the process of building the circuit, 2 stamps went bad on me! I am not
sure what happened, all I know is that I did handle the circuit during
construction and installation. I did take care in "grounding" myself
as much as possible before each time I handle the circuit. On both
occasions, the chip simply went dead. It does not even respond to the
PC when I am trying to access it.
Has anybody had this type of sensitive behaviour from the S2? If that
is a usual trait with the S2, what is the best way of protecting the
circuit once it is out of my hand and in the hand of the users in the
case of commercial products which I am working on for my next project?
Thanks...
Al Najjar
I have build a simple circuit using S2 and it works beautifully,
handling two motors, a relay and the input of 3 switches. However, in
the process of building the circuit, 2 stamps went bad on me! I am not
sure what happened, all I know is that I did handle the circuit during
construction and installation. I did take care in "grounding" myself
as much as possible before each time I handle the circuit. On both
occasions, the chip simply went dead. It does not even respond to the
PC when I am trying to access it.
Has anybody had this type of sensitive behaviour from the S2? If that
is a usual trait with the S2, what is the best way of protecting the
circuit once it is out of my hand and in the hand of the users in the
case of commercial products which I am working on for my next project?
Thanks...
Al Najjar
Comments
relay have any type of 'spike' protection ?
Chris
Original Message
From: <alnajjar@s...>
To: <basicstamps@egroups.com>
Sent: Thursday, December 14, 2000 8:23 AM
Subject: [noparse][[/noparse]basicstamps] Sensitive to static
> Hello
>
> I have build a simple circuit using S2 and it works beautifully,
> handling two motors, a relay and the input of 3 switches. However, in
> the process of building the circuit, 2 stamps went bad on me! I am not
> sure what happened, all I know is that I did handle the circuit during
> construction and installation. I did take care in "grounding" myself
> as much as possible before each time I handle the circuit. On both
> occasions, the chip simply went dead. It does not even respond to the
> PC when I am trying to access it.
>
> Has anybody had this type of sensitive behaviour from the S2? If that
> is a usual trait with the S2, what is the best way of protecting the
> circuit once it is out of my hand and in the hand of the users in the
> case of commercial products which I am working on for my next project?
>
> Thanks...
>
>
> Al Najjar
>
>
>
can give off a large kickback voltage when the magnetic field collapses as
they turn off, this can fry a stamp. The safe practice is to use seperate
Voltage sources for High current devices and Low current devices but keep a
common ground. If you're paranoid you can use optoisolation to protect
you're Stamp but thats only necessary for HVAC applications (at least I
believe that's the case). Stamps are technically static sensitive, however,
that shouldn't be a problem unless you are in an extremely static prone
area. At least that's what they say in the manual. Thought I'd explain why
we are addressing relay and motor setups rather than static. Good Luck.
--Jason
>>Do you have the relay isolated from the stamp via a transistor? and does
the
>>relay have any type of 'spike' protection ?
>>Chris
>>
Original Message
>>From: alnajjar@s...
>>To: basicstamps@egroups.com
>>Sent: Thursday, December 14, 2000 8:23 AM
>>Subject: [noparse][[/noparse]basicstamps] Sensitive to static
> Hello
>
> I have build a simple circuit using S2 and it works beautifully,
> handling two motors, a relay and the input of 3 switches. However, in
> the process of building the circuit, 2 stamps went bad on me! I am not
> sure what happened, all I know is that I did handle the circuit during
> construction and installation. I did take care in "grounding" myself
> as much as possible before each time I handle the circuit. On both
> occasions, the chip simply went dead. It does not even respond to the
> PC when I am trying to access it.
>
> Has anybody had this type of sensitive behaviour from the S2? If that
> is a usual trait with the S2, what is the best way of protecting the
> circuit once it is out of my hand and in the hand of the users in the
> case of commercial products which I am working on for my next project?
>
> Thanks...
>
>
> Al Najjar
>
>
>
not have any transients that would kick back. The two servos are
using a separate power source, but have connected their ground to the
ground of the stamp to ensure stable voltage levels. This is
incidently how it is described in the stamp manual.
I am not aware of any needs to hook a SS relay to the Stamp through an
opto-isolator or transistor! In any case the circuit is now working
smoothly, once it installed.
my concern is common handling. So you think that it shouldn't be that
suceptible to static! Do you know of any way of shielding it from
possible static?
many thanks...
al najjar
--- In basicstamps@egroups.com, "Jason Sperry" <jsperry1@s...> wrote:
> Also, are the motors on a seperate voltage source from the Stamp.
Motors
> can give off a large kickback voltage when the magnetic field
collapses as
> they turn off, this can fry a stamp. The safe practice is to use
seperate
> Voltage sources for High current devices and Low current devices but
keep a
> common ground. If you're paranoid you can use optoisolation to
protect
> you're Stamp but thats only necessary for HVAC applications (at
least I
> believe that's the case). Stamps are technically static sensitive,
however,
> that shouldn't be a problem unless you are in an extremely static
prone
> area. At least that's what they say in the manual. Thought I'd
explain why
> we are addressing relay and motor setups rather than static. Good
Luck.
>
> --Jason
>
>
>
> >>Do you have the relay isolated from the stamp via a transistor?
and does
> the
> >>relay have any type of 'spike' protection ?
> >>Chris
> >>
Original Message
> >>From: alnajjar@s...
> >>To: basicstamps@egroups.com
> >>Sent: Thursday, December 14, 2000 8:23 AM
> >>Subject: [noparse][[/noparse]basicstamps] Sensitive to static
>
>
> > Hello
> >
> > I have build a simple circuit using S2 and it works beautifully,
> > handling two motors, a relay and the input of 3 switches. However,
in
> > the process of building the circuit, 2 stamps went bad on me! I am
not
> > sure what happened, all I know is that I did handle the circuit
during
> > construction and installation. I did take care in "grounding"
myself
> > as much as possible before each time I handle the circuit. On both
> > occasions, the chip simply went dead. It does not even respond to
the
> > PC when I am trying to access it.
> >
> > Has anybody had this type of sensitive behaviour from the S2? If
that
> > is a usual trait with the S2, what is the best way of protecting
the
> > circuit once it is out of my hand and in the hand of the users in
the
> > case of commercial products which I am working on for my next
project?
> >
> > Thanks...
> >
> >
> > Al Najjar
> >
> >
> >