Film-Tech Forum ARCHIVE: NEC Overtemp Warning

This is topic NEC Overtemp Warning in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Jim Cassedy (Member # 4115) on 06-20-2016, 07:10 PM:

I logged in remotely to an NEC 3200S at a theater after they told
me their tail lights were red and there was an "over temp" warning
on the LCD display.

But when I go through the error & temperature logs, I see nothing
really out of the ordinary, & there is no "specific" over temp warning
activity on any of the sensors. (DMD, Bulb, Exhaust, LPSU, etc)

Alarm had already cleared by the time I remotely logged in, but they
said this happened yesterday too. Any idea what's going on here?

Shows are running OK, but..... I don't like to ignore warnings!

>I know we've been having extra high temperatures here on the West
Coast yesterday and today, but I don't have any reason to believe it's
any hotter in the booth than usual. They have good Air Conditioning.

Posted by Justin Hamaker (Member # 2165) on 06-20-2016, 09:41 PM:

Is the roof exhaust fan fully operational? Is there an external fan on top of the projector which might be failing? A switch for a roof exhaust which is getting accidentally turned on - or a breaker not getting turned on?

For the warning to go away on it's own suggests some kind of environmental issue.

Posted by Jim Cassedy (Member # 4115) on 06-20-2016, 09:55 PM:

Unfortunately, Justin, I can't get to that theater tonight.

I've asked the staff the same questions you brought up,
but to be honest, they know nothing about anything and
there's also a language barrier, so talking to them is
rather useless.

After my last post, however, I re-logged back into the
projector, & I see that the "over-temp" alarm WAS defined,
but I just missed seeing it the first time because I was
busy 'multitasking' several other things when they called.

AH HA! Here's a good clue to the cause! [Razz]

I've got a projection-tech friend of mine to head
over there and takalooksee at exactly what's going on.

Posted by Mark Gulbrandsen (Member # 72) on 06-20-2016, 10:10 PM:

It'either lamp house filters or exhaust blower...

From the NEC Error Code List for Error 171

1. Check the ambient temperature. It should be 35 degC or lower.
2. Check if there is any problem on suction air and exhasut air.
3. Check the air filter clogging.
4. Check if the ventilation system is operated with required specification.
5. Check the TSENS PWB

Posted by Steve Guttag (Member # 268) on 06-21-2016, 09:52 AM:

Everytime I've had an NEC overtemp, it was the exhaust not pulling enough air. Fix the exhaust and likely the error will go away (except the NC900...it overtemps on the intake).

That error (171) points to the LPSU complaining on its input and since it is a 3200, that is a separate power supply. I'd check it to see if its intakes are clogged and that your room temp is reasonable (below 80-degrees).