stamps and SCR''s
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IF you want to phase angle fire and SCR, You need to make a comparator which
will accept a voltage for the stamp and use this voltage to phase angle
fire the SCR. In other words do it in analog, let the stamp control the
analog voltage, I did it a long time ago. It works well for 3 phase too.
Sincerely,
Ron A.
Original Message
From: Lee Harker <harker@a...>
To: basicstamps@egroups.com <basicstamps@egroups.com>
Date: Friday, May 12, 2000 7:09 PM
Subject: RE: [noparse][[/noparse]basicstamps] stamps and SCR's
>Chris,
>I don't think you'll have much luck with phase angle firing with a Stamp
>because of the speed. Each cycle of 60hz only takes ~16mS and the
>instruction time on a stamp is around a mS. The math ain't too good. With
>three phase the problem is worse. Someone may have figured a way around
>this but I haven't seen it.
>
>
>At 01:34 PM 12/5/00 -0400, you wrote:
>>Lee:
>>
>>Thanks. I'm already using opto's for control of 120V relay coils. I
>>should have been more clear. My focus is on Phase angle firing of
>>the SCR's with the stamp output. I would like to accomplish this
>>with single phase and three phase back-to-back SCR arrangements. Is
>>this an unusual application for a stamp?
>>
>>Chris
>
>Lee Harker
>258 Metals Development
>Ames Laboratory
>Iowa State University
>
>
>
>
will accept a voltage for the stamp and use this voltage to phase angle
fire the SCR. In other words do it in analog, let the stamp control the
analog voltage, I did it a long time ago. It works well for 3 phase too.
Sincerely,
Ron A.
Original Message
From: Lee Harker <harker@a...>
To: basicstamps@egroups.com <basicstamps@egroups.com>
Date: Friday, May 12, 2000 7:09 PM
Subject: RE: [noparse][[/noparse]basicstamps] stamps and SCR's
>Chris,
>I don't think you'll have much luck with phase angle firing with a Stamp
>because of the speed. Each cycle of 60hz only takes ~16mS and the
>instruction time on a stamp is around a mS. The math ain't too good. With
>three phase the problem is worse. Someone may have figured a way around
>this but I haven't seen it.
>
>
>At 01:34 PM 12/5/00 -0400, you wrote:
>>Lee:
>>
>>Thanks. I'm already using opto's for control of 120V relay coils. I
>>should have been more clear. My focus is on Phase angle firing of
>>the SCR's with the stamp output. I would like to accomplish this
>>with single phase and three phase back-to-back SCR arrangements. Is
>>this an unusual application for a stamp?
>>
>>Chris
>
>Lee Harker
>258 Metals Development
>Ames Laboratory
>Iowa State University
>
>
>
>