NEC 900C Fan Exchange error

[Randy Stankey]

I'm an electronics inspector and, even from the admittedly "fair quality" photo, it's easy to tell that the board is no good.

There are a couple of components that look suspect to me and, if I could see a clearer picture, I'm sure there would be more. It's plain to see that the solder on the pins of that integrated circuit at the center of the image is corroded and several of the pins are shorted together. Like others say, it's likely to be caused by poor cleaning at the time of manufacture. It also could be contaminated lead-free solder, too. Does the surface of the dull solder look rough and grainy? That's a sure sign of contaminated solder.

If the person running the stencil machine didn't clean the machine between runs, it's easily possible for lead solder to contaminate the mix. It doesn't take much. Less than 1%.
If the contamination level is low, the parts might pass inspection but the part will fail prematurely.

If you have several of these boards, I'd be tempted to check the serial numbers and manufacturing dates. If you find a pattern, I suggest reporting it to Christie. I'd say that this defect, regardless of age, should be replaced because it's unfit for its purpose.

Most electronics are made according to three classes with respect to manufacturing specs and inspection. Class-1 is the lowest for general, consumer use. Class-3 is for medical, military and other critical uses. Class-2 is for industrial and mission critical use and that's what I would expect digital cinema equipment to be made under.

If that board came across my inspection station, I'd probably fail it at Class-1.

[Daniel Silva]

The NECs may be a PITA to disassemble and reassemble but even including the labour they are far more cost effective to maintain VS their Barco counterparts. This is the price you pay for not needing to "dig in". Take a formatter failure for example. With a Barco you remove the light engine and put in a different one at a cost of many, many, many thousands of dollars and a total service time of 1 hr. With an NEC you spend maybe 2.5 hours of labour and less than $1K in parts that can be changed in the field. Sure it would be nice if the projector was a little roomier inside to facilitate the removal of the light engine but it's certainly not a deal breaker. It'd also be nice if they put and handle on the prism so you didn't need their little lifter tool. This is the same problem with any of the "modular" designs when it comes to parts but Barco and Christie have the most examples of any equipment I've ever serviced. You have a Christie coolant pump fail? You're replacing the pump, rad, tubing and connectors. You have a lamp explode in a smaller Christie or a Barco, you're buying the whole lamp house, not just the reflector. I'm not saying NEC is perfect but they really can't be beat for service cost with their individual service parts. Barco is realy great though for limiting down time if you have the budget to keep spare parts on hand.

As for doing a complete fan service, I've never replaced an NEC fan at warning time. In a clean booth environment with regularly changed filters, I"m comfortable letting them go 40K or 50K hours. At that point in a projector's life, I'm willing to spend a bit of time doing some TLC on it. Odds are, there are other things that need attending at that point anyways.

hello Greg , this is Daniel From Chile , just bought a new NEC NC2000 , it´s been strored for 9 years , it only shows 10 hours of use .
the blue DMD has a problem , not sure if it is a formater problem or maybe just a loose wire , just starting to look inside this week . I just finnished all the upgrades , and ICP reactivations with no problem .
I´m intereste on the formater replacement you mentioned , do you have maybe a procedure for it , that you can share with me . ? attached is a picture of the fsailure on the Blue . red and green are OK .

[Mark Gulbrandsen]

With NEC fans, I replaced the ICP, AC On, and Power On after 5 years as those are critical fans. Always did them on projectors that were a multi day drive away. In multiplex's, I replaced those same three fans, but kept the used fans in the booth to use as spares in those same positions. Otherwise I never had any fan failures in NEC S2. Although since retirement it's certainly possible that there could have been a few failures. All I can say is that NEC used some sooper dooper type of long life fans! I only ever saw really long life fans in the past, in Broadcast equipment.

As far as changing formatters, When I attended one of the early NEC training classes that was held at Strong, They did indeed show us how to switch out a formatter. I remember Greg saying they can only do it if they happen to have a light engine that was sent in for service while the class was going on. In my case it was a S-1 NEC engine. But S2 is very similar. Just be wary of all the floating gold contacts that may fall out on the floor if you have the particuluar formatter in the wrong position. Also, you need the appropriate torque tools to make sure the replacement formatter is properly snugged in... (inch ounces I believe).