Well that depends on how you are energizing them. I'm using the WD7S control
board and he uses a simple open collector (active low) to energize the
relay. The other side of the relay will have +24 VDC on it. They don't
require much current so if you wanted to put a pull down resistor on them
you could. 220 ohms would be fine. I won't have them on my relays. An open
collector has no leakage between emitter and collector when there is no
voltage (bias) on the base.
It won't hurt to have the resistor there though. Just more current for the
source.
73
Jim W7RY
----- Original Message -----
From: "Bob Maser" <bmaser@tampabay.rr.com>
To: "Jim W7RY" <w7ry@arrl.net>
Sent: Wednesday, January 28, 2009 6:15 PM
Subject: Re: [Amps] Crydom Solid State Relays
>I was told that the resistor was to bleed off the voltage after the DC was
> removed.
>
> Bob
> ----- Original Message -----
> From: "Jim W7RY" <w7ry@arrl.net>
> To: "Bob Maser" <bmaser@tampabay.rr.com>; "AMPS" <amps@contesting.com>
> Sent: Thursday, January 29, 2009 2:09 AM
> Subject: Re: [Amps] Crydom Solid State Relays
>
>
>> You really only need 2 relays. One for one side of the AC line and one to
>> short out the step start resistor on the other. There is voltage drop
>> through those relays. About 1.4 volts as I remember.
>>
>> And yes. .01 across the "coil" leads of the SSR is a good idea. What
>> would
>> the resistor be for?
>>
>> 73
>> Jim W7RY
>>
>> ----- Original Message -----
>> From: "Bob Maser" <bmaser@tampabay.rr.com>
>> To: "AMPS" <amps@contesting.com>
>> Sent: Wednesday, January 28, 2009 5:07 PM
>> Subject: [Amps] Crydom Solid State Relays
>>
>>
>>> The power supply of my new amplifier will be using 3 40A Crydom SSR
>>> relays,
>>> One on each leg of the 240VAC and another in one leg to short out the
>>> step
>>> start resistor. I have been planning on using the SSR's w/o any
>>> resistors
>>> or capacitors across the control connections but I have been advised
>>> that
>>> I
>>> should put resistors and capacitors across the control connectors to
>>> prevent
>>> RF from affecting the SSR function and possibly causing "chatter". I
>>> would
>>> appreciate some feedback from the group. I don't believe that Jerry
>>> Pittenger K8RA used anything in the 3CX1500D7 amp that was featured in
>>> the
>>> 2006 ARRL Handbook.
>>>
>>> Bob Maser W6TR
>>>
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>
>>
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>>
>>
>>
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>> 1/23/2009 6:54 PM
>>
>
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