# Eaton S801T Soft Start Fault



## wildleg (Apr 12, 2009)

Up in the sky !

It's a bird !

It's a plane !

No . . it's Jraef !


too bad you can't add a pole to the middle of a thread. 
It would have 2 options:

A) Fried
B) Sounds like a job for Jraef

(I'm assuming you called the 800 # ? (or 877-Eatone or 877-AteOne or whatever the heck it is now)


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## Cow (Jan 16, 2008)

It sounds like it's junk to me Micro, at this point I'd usually try to hunt down a phone number to Eaton just to run it by one of their techs before I threw it in the trash.

Then I'd try and convince the customer to let me buy almost anything else but Eaton. I don't care at all for their programming menus in their VFD's, I'm not sure how their soft starts rate though...


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## John Valdes (May 17, 2007)

Maybe you could reset all values to factory values? Factory reset option.
If you have a manual, it will be in the parameter groups.


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## macmikeman (Jan 23, 2007)

I have a game plan for stuff like this.

Replace with another unit. Charge large.


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## micromind (Aug 11, 2007)

I kinda figured it was shot, or at least the PT module is. I figured I'd at least see if anyone knew whether or not parts were available. Generally they're not. 

I'd like to replace it with an A/B but it's in an MCC and it won't fit in the bucket and there's not room to remotely mount it.


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## JRaef (Mar 23, 2009)

That series of Soft Starter was called the IT Series, and being that it is Cutler Hammer (CH), I always called them CHIT starters. probably one of the worse soft starters on the market at the time. They're still bad, but the industry has produced even WORSE ones now, so they went up by default...

The biggest issue I've always had with those is the heat sink. They have NONE! They just clamp the SCRs between some bus bars and call it good. Made the starter small, but totally useless for starting large loads. If you were using them on centrifugal pumps, they survived, but anything else and they crapped out. When they first came out, rumors were Eaton had a field failure rate of around 50%! What they did to slow that failure rate down was to come out with a complicated duty cycle chart system with 7 different "application profiles" that essentially had you over sizing them, up to 3X the initial rating! 

With no heat sinks, the SCRs cannot be on for long. What they really do is that inside of that starter there is an integral bypass contact across each pole, and DC controlled coils for them (which is why you need the DC power supply). The control board RAMPS the DC into the coils so that the contacts close gently and quietly, so quietly that you don't know it happened unless you look on a scope. If you set the soft starter ramp time for 45 seconds, the lack of heat sinks meant the SCRs could only handle about 7 seconds, so they went ahead and closed the bypass in 7 seconds and you were across-the-line. But they kept flashing the "Ramping" LED for all 45 seconds, counting on the fact that people cannot tell the difference in the sound of a ramping motor and an accelerating motor. Total scam, gave the industry a bad name.

In the case of your starter, most likely that one of the bypass contactor coils has welded, that's why you can't reset it. 

An A-B SMC-3 might fit in that space, they are smaller than the SCM-Flex. If not, you might be able to replace one entire pole assembly (SCR pair + heat sink + bypass contact). Put power on it and measure the voltage drop across each pair, L to T. The one with the shorted bypass will have no voltage drop.


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## micromind (Aug 11, 2007)

This actually explains a lot.......

About 15 years ago, I did a sewer plant in Fallon, it has 6 C/H soft-starts. 3 were 75HP the other 3 were 125HP. 

I'm pretty sure that all 6 had failed at some point in the first couple of years. 

I finally recommended that they be replaced with A/Bs (I don't remember the model) and it was a bear mounting them as the C/Hs were smaller. I ended up mounting them in cans above the MCC. 

As far as I know, the A/Bs are still working.


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