Many years of working with the things I agree ... mostly. Although they
normally fail shorted, they do occasionally fail "leaky" in a mode from
low to high resistance, but rarely open. Not never, but rarely.
So, it's bad enough to have them fail shorted, but then a small
percentage will leave you guessing.
If they fail other than shorted and under load it can get real smelly in
there. OTOH they can fail with enough resistance that the circuit won't
work, but is quite capable of electrocuting you.
73
Roger (K8RI)
Mike Saculla wrote:
> When solid state relays fail, they fail in the shorted condition. One of
> their downfalls.
>
> Mike K6MDS
>
>
> From: garyschafer@comcast.net
> To: Amps@contesting.com
> Date: Thu, 4 Mar 2010 15:53:17 -0500
> Subject: [Amps] Solid state relays and step start
>
> Has anyone had problems using a solid state relay to short out the step
> start resistor in a power supply?
>
> I have heard of problems of not enough current thru the SS relays (when amp
> is in standby) when used as the primary on/off relay. Sometimes a resistor
> has to be placed in parallel with the transformer primary so the relay works
> properly.
>
> When used in a step start circuit the current could be quite low as well as
> the voltage at the relay due to the resistor across the relay. Any issues
> here?
>
> 73
> Gary K4FMX
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|