Re: {Collins} Connecting a KWM-1 to a 30L-1

Now I am shaking in my boots, what with 2000 volts wandering around in my 30S-1 and close to 1000 volts in my 32S-3 and now to find out that a lousy 115 volts puts my life in jeopardy, Colin you need to relax and slow down just a bit, I have been around high voltage all my life and believe I understand how to be cautious around electrical power, this ain't my first rodeo, and BTW according to the manual 120 VAC is normal on pin 20 ????

73's Dutch WB7DYW
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--- On Fri, 6/10/11, Colin Lamb <k7fm@xxxxxxxxxxxx> wrote:

From: Colin Lamb <k7fm@xxxxxxxxxxxx>
Subject: Re: {Collins} Connecting a KWM-1 to a 30L-1
To: "Dutch Maurer WB7DYW" <wb7dyw@xxxxxxxxx>, "J Allen Call" <call.jac@xxxxxxxxxxx>
Cc: collins@xxxxxxxxxxxxx
Date: Friday, June 10, 2011, 1:42 PM

"I used a 115 VAC relay connected to pin #20 on J5 to ground, worked fine..."

It might work fine, but there a caution is in order.  The 30L-1 manual specifies a dc relay connected to pin 20 of the KWM-1.  On page 1-5 of the 30L-1 manual, 1.3.3 and 1.3.4 cover the KWM-1 connections.  If the KWM-1 serial number is below 861, pin 20 is not connected and an internal connection to the 260 volt dc line is made.  This provides the dc at pin 20 for the relay.  

As I understand the facts, Dutch has 120 ac volts on pin 20 and he connected an ac relay coil between pin 20 and ground.  Although it works, it would not be safe, because the 120 volt return is the chassis.  This is unsafe.  In addition, if the KWM-1 is sold, it could become lethal.  

AC should not be coming from pin 20 and should not be returned to ground.  Safety first!!!!!

Colin Lamb  K7FM

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