>=20
> The diode across the coil method isn't the best either, if you care how q=
uickly the relay opens.
> Slow opening can result in contact welding.
>=20
> The best method is a Zener from Collector/Drain to ground.  Set the Zener=
 voltage a bit below the transistor VCE/VDS rating.
> This speeds up the collapse of the current in the coil by as much as 3x

Dave is right, this will help get rated life out of the relays. They are *n=
ot* rated with diodes directly across the coils. You may be able to use one=
 TVS or Zener (total)  and one diode per relay.

Spehro Pefhany=20

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