On 8/28/2013 9:03 PM, Carl Denk wrote:
> I have several digital controlled relays @ 12 VDC coils, the coils are
> powered from a PLC. If 2 or so relaycoils are connected in parallel,
> should I have one diode across the coil terminals of every relay? If
> only one relay requires a diode, should it be at the nearest or farthest
> coil from the driver. The relays are located within inches of each other
> and more than 20' of cable to the driver IC. More than one relay is
> required since I am using 4PDT relays and I have more than 4 circuits to
> switch.
>
> Thanks ahead for replies :)


Closest to the relay, possibly between the pins if the relay layout=20
allows it.  I typically use 1n4004 diodes because they are a common part=20
and cheap.  One per relay is what I would do.

Mark

--=20
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