Film-Tech Forum ARCHIVE: wow first nc900 lamp made it to warranty

This is topic wow first nc900 lamp made it to warranty in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Gordon McLeod (Member # 33) on 12-10-2014, 01:49 PM:

Wow we have had probably our first pair of NEC 900c lamps make it to the end of their warranty period not the usual bang at 250-300 hrs

Posted by Carsten Kurz (Member # 5396) on 12-10-2014, 04:44 PM:

Do you know when these bulbs had been installed? Do you know at what current/% rating they have been run?

- Carsten

Posted by Mark Gulbrandsen (Member # 72) on 12-13-2014, 04:51 PM:

I've had quite a few make it to 3K hours.

Posted by Steve Guttag (Member # 268) on 12-13-2014, 06:17 PM:

I've had zero make it thus far but we were not the first putting in the NC900.

Posted by Steve Guttag (Member # 268) on 12-24-2014, 05:58 AM:

Just had one get to about 1750 before blowing...still at zero making it the distance.

Posted by David J Hilsgen (Member # 2614) on 12-24-2014, 04:03 PM:

What is the warranty on these bulbs

Posted by Steve Guttag (Member # 268) on 12-24-2014, 08:53 PM:

Supposed to be 3000-hours.

Posted by Frank A Cianciolo (Member # 7941) on 12-27-2014, 07:48 PM:

I've had my NEC 900 for a year - both bulbs have blown - the first at 600 hrs, the second at 900. Strong claims to have not received my first bulb, so I never got any credit for it blowing early - and I am just shipping them the second, keeping note of the tracking number this time!

Posted by David J Hilsgen (Member # 2614) on 12-27-2014, 08:50 PM:

Thanks steve for the imfo, i service a theatre in foley, mn ,that i installed 3 of the nec 900. i have 1 screen burning both bulbs at 100%, the other 2 screens 1 bulb at 80%, they`ve been in for a little over a year, just over a 1000hrs still good light .

Posted by Richard May (Member # 2627) on 12-27-2014, 09:40 PM:

Good to hear. I'm putting more and more of these in.

Posted by Steve Guttag (Member # 268) on 12-27-2014, 10:52 PM:

So if you are only burning one lamp...what is the other lamp doing? Unless there has been a software change I'm unaware about, if the one you are using burns out, nothing will bring the other on line. Furthermore, the software isn't smart enough to even rotate the life of them (e.g. alternate which lamp gets lit to keep the hours about even).

Aside for the dramatic color shift when setting the lamp levels, I've noted a bit of a "gap" between the light level of both lamps at minimum versus one lamp at maximum.

Posted by Steve Guttag (Member # 268) on 12-29-2014, 03:57 PM:

Note...it is important to be in NEC's 4.214 (or 4.215) for extended lamp life. They changed how the lamp shuts down so it doesn't cool too fast. They determined that the lamps were cooling too fast and causing problems. Starting on 4.214, the lamps first drop to 75% of power for 5 seconds then they go off. There is a Service Bulletin on this PJ-14-013-00-E

It notes that the newer ballasts also have an improved method of controlling the lamp to improve life. However, it is a hardware update, not software (new ballasts and ballast firmware 0207 instead of the older ballast and firmware 0204).

Posted by Carsten Kurz (Member # 5396) on 12-29-2014, 05:37 PM:

It's interesting that most reports of blown 330W/350W bulbs for the NC900C and the Sony 515/510 (more or less identical bulbs) went with lamps running at LOW operating currents. There are no official statistics, but I know a lot of cinemas having had issues with the 330W lamps in the Sonys had problems with early lamp failure while running the lamps at 80%. And the problem went away when they started to run them at 90% or more. So I'm wondering how this relates to this scheme of running the lamps at 75% before powering off in order to prevent lamp failure due to 'overcooling'. Also, the Sony 450W bulbs do not suffer from this issue.

- Carsten

Posted by Steve Guttag (Member # 268) on 12-29-2014, 09:47 PM:

They only run them at 75% for 5 seconds...what they found, from what I read, is that it was thermally shocking the lamp to cool it too fast...so they step it down rather than just kill it. There is a chart in the bulletin showing the increased lamp life and what the cool down rate is before 4.214 and after.

I'll say this...the lamps that I have blow are running on 4.214 though not for their entire life.

Posted by Gordon McLeod (Member # 33) on 12-29-2014, 10:34 PM:

still having failures at 600hrs approximately

Posted by Richard Fowler (Member # 893) on 12-30-2014, 08:15 AM:

Sony has a new Ushio re-designed bulb for the 515 / 615... model LKRM-U331. They recommend v1.30 or more current software.

Posted by Marco Giustini (Member # 4544) on 12-30-2014, 08:51 AM:

Did you mean 510 or is there a new model on the wild?

Edit: Ok, it's the industrial version

Posted by Joris Springer (Member # 4175) on 01-08-2015, 06:44 PM:

Wait, are you telling me there are worse lamps than Osram and Philips???