Check the reel to make sure that you don't have a plain blue plastic reel.
Determine that it is dissipative with a field meter. Check the tape to see
if it is charged prior to pulling it off the reel. What is the sensitivity
of the parts on the reel? An air ionizer may not work if the charging is
generated as the tape is pulled from the reel. The ionizer will neutralize
the exposed tape after the tape has been charged. This is demonstrated by
pulling the tape off a roll of transparent tape. This will not prevent your
components from damage from the charged device model if they are grounded
before the charge is neutralized.
Make sure that your purchasing department purchased your components on
static dissipative reels. All ionizers must be balanced to be effective,
otherwise they will charge the components. Many ionizers are auto balance
type and do not have an external adjustment.
Al Cash
> ----------
> From: Neil Maloney[SMTP:[log in to unmask]]
> Reply To: TechNet E-Mail Forum.;Neil Maloney
> Sent: Monday, May 04, 1998 12:22 PM
> To: [log in to unmask]
> Subject: [TN] ESD buildup on SMT reels
>
> Greetings Technet!
> I've got a problem.
> My operator just put a new 7"reel of type 1210-07 1.5K 1/2W resistors
> (QTY 4000) on our Mydata PNP machine, only to find that most of the
> components are sticking to the cover sheet as it is being pulled back from
> the tape. Upon investigation, I discovered nothing adhesive or "sticky"
> on
> the cover sheet, but the whole reel registers 500 - 3Kv on the ESD meter.
> The reel itself is of a typical blue plastic "ESD safe" variety just
> like the dozen others on the machine that read "0" on the meter. So it
> must
> be the tape, which is made of "clear" plastic.
> My question is .... is the tape itself made of an inferior grade of
> plastic, or was the reel subjected to a massive static charge? My entire
> facility, including the bathrooms, is ESD safe. Our inventory is stored in
> ESD safe bins. Everybody wears ESD straps here, besides, I don't think Dr.
> Tesla himself could generate enough static on his person to zap this reel,
> without blowing a finger off.
> The supplier has not returned our phone calls. (Imagine my surprise.)
> Seriously, I am worried that something got in here that is our of our
> control.
> Has anybody else had this problem?
> Did the supplier use bad plastic?
> Is the reel of parts finished?
> Can I dissipate this charge, or will it build up again when the reel is
> back on the machine?
> Do vendors ever answer their phones?
>
> Thank you in advance for your replies.
>
>
>
> Neil Maloney, Service Technician
> Contemporary Control Systems,Inc
> 2512 Wisconsin Ave. Downers Grove, IL.60515 USA
> (630) 963-7070 x132
> E-mail: [log in to unmask]
> URL: http://www.ccontrol.com
>
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