Film-Tech Forum ARCHIVE: NEC NC2000C Randomly Shutting Down

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Posted by Justin Hamaker (Member # 2165) on 07-22-2016, 10:27 PM:

I'm researching an issue that happened today at our sister theatre. One of our NEC NC2000Cs just randomly shut down and went into standby. The projector did not throw any errors and there did not appear to be any heat issue.

I have reviewed all the logs and I don't see any kind of errors, and no other events which might be related.

This issue has happened once or twice before, but the timing is so random and spread out that it's difficult to draw any kind of links in terms of time of day, content, format, etc.

I know projector shut downs are usually related to overheating, but there was no apparent heat issue with this projector. I called the Strong NOC and they indicated they are seeing things like this due to overloaded power girds resulting in a dip in amperage enough for the projector not to be able to keep the lamp lit.

Anyone have any other ideas?

Posted by Stephan Shelley (Member # 8587) on 07-23-2016, 12:11 AM:

Are the electronics on an UPS? If not putting them on one would eliminate voltage fluctuation issues.

Posted by Justin Hamaker (Member # 2165) on 07-23-2016, 01:07 AM:

The projector side is on a UPS, but not the lamphouse side.

Posted by Stephan Shelley (Member # 8587) on 07-23-2016, 01:32 AM:

Assuming the UPS is working properly a power dip might cause the lamp to go off but the projector should not go into standby. Or am I misunderstand what the issue is.

One other thing that comes to mind is a white power switch issue on the projector. They are known to have problems and maybe it once in a while looses contact interrupting the power momentarily.

Posted by Steve Guttag (Member # 268) on 07-23-2016, 04:28 AM:

I think Stephen hit the nail on the head on this one. If there is nothing in the logs a power problem would show up in the logs when the LPSU lost power...simulate it, Kill the LPSU power and see what shows up in the logs. But if that isn't there, look elsewhere.

I'd say it is either the power switch or your UPS (or the connectivity thereof...make sure that the IEC cord is securely in and has that strain relief secure to keep it in.

Posted by Mark Gulbrandsen (Member # 72) on 07-23-2016, 10:08 AM:

I've never had a white power switch cause intermittent shutdown. In fact they have always gone bad stuck in the off position because of a little plastic rod inside that snaps off.

I too would suspect the UPS before anything else, I have had a few UPS failures from allowing the batteries to go beyond their normal life span. You get one that shorts out and its gonna drive the UPS batty and possibly damage it. Tripp Lite recommends replacing batteries ever three to four years which I now do. In some of the Tripp Lites I have replaced batteries in, the batteries were already two years old when the UPS went into service, so they were six years old!! I have not had an LVPS power supply ever fail on an NEC. I have had one ballast failure in an NC-1200 though where it wouldn't reliably light the lamp.

Anyway, I'd bypass the UPS first and eliminate that. There are commercially available Bypass Panels that allow one to safely plug everything in easily. All my locations have at least one of those panels as an immediate back up plan.

Mark

Posted by Stefan Vogels (Member # 5573) on 07-23-2016, 03:28 PM:

In the communicator it is possible to program the projector what to do in case the bulb unexpectedly goes off. It is either cooldown or go to stand-by. It might be set to this last setting and so when the bulb fails the projector goes to standby.

Posted by Stephan Shelley (Member # 8587) on 07-23-2016, 04:08 PM:

To me with this projector if the lamp is off but the projector electronics and fans are on is just a lamp off state. Standby is when the power has just been turned on and the button panel is active. One has to push the power button to take it out of standby to full power lamp off. I know you have to be in the above standby state to reset the lamp hours and they call it standby. Are we all talking about the same thing?

Posted by Justin Hamaker (Member # 2165) on 07-23-2016, 07:14 PM:

Stephen, yes, that's the state I'm talking about. Projector has been powered on, but 'keylock' and power button have not been pressed.

Posted by Stephan Shelley (Member # 8587) on 07-23-2016, 07:21 PM:

I would double check the connections on the projector side from the UPS. Try a different UPS or bypass it.

Posted by Timothy Eiler (Member # 383) on 07-25-2016, 12:53 PM:

Posted by Bob Ezra (Member # 841) on 08-17-2016, 08:34 AM:

Mark

I just had a Tripp Lite SMX1500LCD Digital UPS System fail. Not a battery issue, it failed to turn on (just under 3 yrs old). Fortunately I had a backup on hand.

I am wondering if you can elaborate on "commercially available Bypass Panels that allow one to safely plug everything in easily."

Thanks

Posted by Steve Guttag (Member # 268) on 08-17-2016, 09:23 AM:

They are commonly called "transfer switches" and are something we build into our automation systems now...if either the city or UPS power is there, the show runs.

A poor man's transfer switch is to plug everything into a suitable power strip (I like the Tripplite UL600CB) and then plug THAT into the UPS...if the UPS fails, plug the power strip into the outlet that the UPS was plugged into and you are back up much faster than having to replug everything back in again.

Posted by Sam D. Chavez (Member # 1841) on 08-17-2016, 10:21 AM:

Suitable is the key word here. Not some cheap outlet strip with a thermal breaker that will trip under load and leave you off screen.

Posted by Carsten Kurz (Member # 5396) on 08-17-2016, 10:57 AM:

We solve that on Doremis by feeding one of the redundant power supplies from the UPS, the other directly from mains. So the dual power supplies add another level of redundancy.

- Carsten

Posted by Bob Ezra (Member # 841) on 08-17-2016, 11:04 AM:

In my case the 220 input to the ups comes via plug from MIT pedestal power dist unit .

Then there are the , not typical, male output plugs. 2 for the Doremi and 1 for the Barco electronics.

So a 220 receptacle would need to be installed to plug in a strip.

Could not find the tripplite model suggested by Steve.

So still wondering what power strip would work as a backup?

Posted by Leo Enticknap (Member # 534) on 08-17-2016, 11:07 AM:

quote: Stefan Vogels
It is either cooldown or go to stand-by. It might be set to this last setting and so when the bulb fails the projector goes to standby.

If it is set to standby, I'd strongly suggest changing it to a cooldown (length depending on how big the bulb is, e.g. 5 mins for a smallish bulb, up to 15 for a 7kW). Killing the power to a bulb without cooling ventilation will destroy a bulb very effectively: best case scenario is flickery and envelope blackening, worst is kaboom.

I did have a problem a few months back caused by one of my co-workers forgetting to turn on the extract fan for an NC3200S. He ran the bulb with no air extraction for 4-5 hours before I arrived and discovered the booth like a sauna and the top of the case hot enough to fry bacon on. After that, the bulb kept going out randomly until it was replaced, but the projector head itself did not shut itself down.

Posted by Mark Gulbrandsen (Member # 72) on 08-17-2016, 11:36 AM:

quote: Leo Enticknap
I did have a problem a few months back caused by one of my co-workers forgetting to turn on the extract fan for an NC3200S. He ran the bulb with no air extraction for 4-5 hours before I arrived and discovered the booth like a sauna and the top of the case hot enough to fry bacon on.

I'd say you have a somewhat dangerous issue with your NC3200S for sure. There is a thermal sensor in the stack of all NEC projectors that will kill the lamp ballast if the temperature goes up too high. Check your logs! When ever I get a call that a lamp goes out its always because the roof exhaust fan has died.

Mark

Posted by Steve Guttag (Member # 268) on 08-17-2016, 12:13 PM:

I mistyped. It is an UL800CB https://www.tripplite.com/waber-by-tripp-lite-10-outlet-industrial-power-strip-15-ft-cord-large-plug-spacing~UL800CB15/

It is a 120V power strip, not a 220. I've gone back and forth on the 220 versus 120 thing. And while MOST things are wide-range power supplies (will run on just about any voltage/frequency) not all are or one would need adapters to plug them into 220...I've just settled on 120V for everything and step-up to 220 for things like the Barco projector (Christie and NEC will work with 120V UPSes).

Tripplite does have Transfer Switched PDUs:

http://www.tripplite.com/1.9kw-single-phase-ats-switched-pdu-120v-16-5-15-20r-2-l5-20p-5-20p-inputs-2-12ft-cords-1u-rack-mount~PDUMH20ATNET/

I've heard mixed on their reliability though.

Posted by Leo Enticknap (Member # 534) on 08-17-2016, 12:16 PM:

I did check the logs, and the bulb flameouts after it was cooked were not caused by an overheat: the bulb just went out. Once the bulb was replaced, the problem went away, so knock on wood, I think we got away without any projector damage.

Posted by Mark Gulbrandsen (Member # 72) on 08-17-2016, 12:59 PM:

Still, My experience with a boat load of NEC's shows them all shutting down in 20 minutes or less when exhaust is left off. Even if just running a 2kw lamp.

Mark

Posted by Leo Enticknap (Member # 534) on 08-17-2016, 02:12 PM:

This was a 3kW (though only running at about 50% power), and was still alight 4-5 hours later. As I say, thankfully, the damage was restricted to the bulb itself.

It's a relatively short and almost straight-up vertical duct from the top of the projector to the fan on the roof (about 4 feet to the outside world, and the projector has its own duct/fan - it doesn't go into a plenum), so maybe there's enough natural airflow there to have kept us out of some much more expensive trouble, thankfully.

Posted by Mark Gulbrandsen (Member # 72) on 08-17-2016, 04:11 PM:

Yes, Thats almost like not having the duct connected at all. I have never seen any damage to any NEC lamphouse components from excessive heat. They all still look like new...

Mark

Posted by Carsten Kurz (Member # 5396) on 08-17-2016, 06:22 PM:

Shouldn't there be airflow sensors preventing the ignition of the bulb when the fan is not running - in EVERY projector? It's hard to take a 3kW (or even larger) bulb is running for 6 hours without cooling...

- Carsten

Posted by Leslie Hartmier (Member # 7053) on 08-17-2016, 07:54 PM:

We had a similar problem using an NC1200C, and it did precisely the same thing - what was occurring in our case (no alarms, no reported errors in the logs), was that the LPS was starting to fail. It occurred twice, (first time, we considered it interesting, but it could have been anything, the second time, we started to look into it, but 'the third time' occurred, like, two days later, which made for an abrupt end to troubleshooting) then a couple days later, the LPS outright failed, which caused the projector to go into standby, after making a most disagreeable racket, tossing an error, then returning to standby, and looking remarkably innocent.

I can confirm that if the LPS has failed or is failing, and/or the communication cable for the LPS is disconnected or not completely in/got dislodged, the projector will have a fit, then will go to standby.

I do not know for certain if this is your problem, but it may be worthwhile to try it out.

One thing you might try if you have the option, is to swap the LPS between a known good projector to see if the problem travels. I have moved a 2kW LPSU into an NC2000C and a 4kW LPSU into an NC1200C (both are using a 2kW bulb) (note: at the time, NEC engineers exasperatedly told me that they wash their hands of such a stunt, but it should work (and it did)) to test. (I even left the 4kW LPSU in, until the replacement came in.)

Good luck!

Leslie

Posted by Mark Gulbrandsen (Member # 72) on 08-17-2016, 08:22 PM:

quote: Leslie Hartmier
the LPS outright failed, which caused the projector to go into standby, after making a most disagreeable racket, tossing an error, then returning to standby, and looking remarkably innocent.

NEC did have a bad run of LVPS on some early NC-1200 units. However, a bad igniter will also cause exactly the same symptoms with that odd sounding shutdown and the projector looking innocent when it's all over. Its such an odd sound that I doubt a Foley crew could even recreate it.

Mark

Posted by Carsten Kurz (Member # 5396) on 08-18-2016, 05:56 AM:

Try to record it next time. Could yield big money from the next StarWars sequel.

- Carsten

Posted by Steve Guttag (Member # 268) on 08-18-2016, 06:02 AM:

I'd always look at the logs. Put them in a spread sheet and graph the temps...you'll see pretty quickly when the exhaust failed and the projector really did "feel" it though it may not have gotten to the point it threw out an error code.

As for every projector having an air flow sensor...Only Christie 20 and 30 series and the Barco B series have them, that I'm aware. Barco's will put up a yellow tail light and complain on the optional touchpanel or Communicator but will let you still run. Christie will shut you down or prevent you from starting in the first place. The two biggest problem with Christie's method is:

1) If the switch bobbles in the slightest, it kills the lamp and won't turn it back on when the error clears so you run a show with out a lamp

2) Their switches fail. They are running very low current through these switches and will give false failures (same with the door switches). In this day an age, an electromechanical switch having to contend with ROHS probably isn't the best solution. But at least let your software have a suitable "Debounce" scheme to avoid nuisance trips.

Posted by Carsten Kurz (Member # 5396) on 08-18-2016, 07:11 AM:

The Sony 5xx doesn't allow the bulb(s) to ignite when the airflow sensor isn't up. However, once the bulbs are lit, a fan failure doesn't switch off the bulbs, but issues a warning. Which makes some sense, I guess. I would then prefer the bulbs to switch off without airflow when a show/SPL has ended, also because some fan issues could be solved while the show is running.

- Carsten

Posted by Mark Gulbrandsen (Member # 72) on 08-18-2016, 12:35 PM:

quote: Steve Guttag
I'd always look at the logs.

Did that just last night after a customer notified me his new HVAC was now in and running and he wanted to know what the projector temps were running. This was one of my most troubled sites where they first lost a GDC server and then two QSC amplifiers because in the summer the booth would top out at 100 Fahrenheit. The new HVAC in this theater now has this booth running about 74 degrees and all projector temps are 20 degrees or more cooler then they were. I actually has the ICP in this place overheat and throw an error, projector didn't shut down though.

NEC has never used airflow switches, only temperature sensors in the stack and other locations through out the projector. I hated those air flow switches in the Christie projectors. I had too many a sail sucked right up the stack. This is an aspect Christie certainly could improve upon for sure. Switches are NOT fool proof and lad free switches do not like to reliably pass really low electrical currents.

Mark

Posted by Frank Cox (Member # 6258) on 08-18-2016, 02:35 PM:

Lad switch?
[Big Grin]

Posted by Mark Gulbrandsen (Member # 72) on 08-18-2016, 04:26 PM:

You bet Laddie!

Posted by Steve Guttag (Member # 268) on 08-18-2016, 08:07 PM:

He meant Lead but really he meant Cadnium. Heavy metals, good for electricity and preventing oxidation.

Posted by Mark Gulbrandsen (Member # 72) on 08-19-2016, 12:15 PM:

I wish they still used cadmium in switches. They would never go bad... Gold plated contacts still seem to be reliable in low current situations though. I have been using a lot of those in Audio gear I build and no failures yet.

Mark