Re: (ET) Sparks!

["Clean Power Supply" <cleanpower att net>]

 I may have misunderstood what you were doing, but here's what you can do:
 With throttle on full speed FORWARD, check for the presence of approx. 
36volts on the coils (small terminals) of both 1A and 2A. Next check 
VOLTAGE across the contacts (big terminals) of both 1A and 2A. Any voltage 
shown should be minimal, representing only the voltage drop across the 
contacts.

On July 22, 2013 at 8:56am -0400, you wrote:
>I do have 2nd speed though, so that means 1A is closing, right?  1A 
>closed would also be MORE current at the downstream side, yes?
>
>Would it make a difference to my Fluke (which is my real concern) if I 
>measure across these contactors rather than from them to battery 
>negative--which was what I was doing?
>
>Thanks.
>
>Thon
>
>On Jul 22, 2013, at 6:24 AM, Harold Zimmerman-Clean Power Supply wrote:
>
>> Sounds like 1A is the one not closing. A reading of approx. 36V on the 
>> coil and almost no voltage across the contacts when running is what 
>> you're looking for. Sounds like current was flowing through the 
>> resistor instead of the contacts of 1A and when you applied your test 
>> lead it tried to flow through there and the lead couldn't handle it.
>> Harold Zimmerman
>>
>> On July 21, 2013 at 1:01pm -0400, you wrote:
>>
>>> I was having problems getting my E12M to move forward and traced it to 
>>> a bad micro-switch.  Replaced and all seemed ok for a short time.  
>>> Now, no high speed (2A).  2A coil has 38v, but no v on its contacts.  
>>> Wanted to check for voltage on 1A contact which should feed 2A.
>>>
>>> With drive motor running in 2nd speed, but lever in high, I touched 
>>> meter probe to the 1A contact (wire #7), got sparks and nearly burned 
>>> my probe in 1/2.  Am fairly certain the probe wasn't touching anything 
>>> else.  Before I ruin a good Fluke meter, or its probe, thought I 
>>> better ask what's going on.  :-)
>>>
>>> Was current being diverted from R2 through the meter?  Or?  I should 
>>> mention I replaced 1A (needlessly) when doing the original 
>>> troubleshooting.  It's a slightly different style contactor than the 
>>> original but don't think it explains this.
>>>
>>> Thanks.
>>>
>>> Thon
>>> _______________________________________________
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>>
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