Dolby cat745 IMB low battery early warning

[Leo Enticknap]

Has anyone actually seen this indicating a low battery?

DSS_cat745_lowbattery.jpg

I ask, because a customer wants me to replace the battery in a cat745 that he says is seven years old. I explained to him the dilemma that we are now all familiar with: the risk that procedure may fail, leaving him with a server and IMB that are effectively e-waste, versus the reality that doing nothing will produce that outcome anyways.

He asked in response if the server gave any warning of imminent battery failure. I remembered that this feature had been introduced in a relatively late software/firmware version (4.8.something IIRC), but I cannot remember ever actually seeing it produce the warning. I wonder, therefore, to what extent we can rely on this. Has anyone ever actually seen this field with a "yes" in it?

[Steve Guttag]

I have NEVER seen it show yes. I agree, there is no good outcome here. The best advice that was given to me is if you are going to do the original battery change to ensure that you give the temp battery a good 30-seconds to a minute before changing the main battery (I'd probably try to measure to verify that the temp battery is actually doing anything)...and then when the new battery is in, same thing...give it at least 30 seconds to a minute before removing the temp battery.

I hate that temporary battery holder too...it has a tab at the top that will make it less easy slipping of a tube over it (to avoid an inadvertent short while messing with the batteries).

If I was in the position, I'd probably try to do the battery swap with the server powered up (though they say it shouldn't make a difference) and DeOxit (D5) things and let that cure too. Heck, I'd be willing to leave the temporary battery in if it wouldn't drag down the main battery (double the chances of a good connection)?

I hear that the chance of failure is 60-70%

Good luck, let us know how it goes!

[Leo Enticknap]

We decided not to attempt the battery swapout, but to keep the projector (and thus the IMB) permanently powered up until the customer is in a position to upgrade.

This is installed in a film school seminar/screening room. Apparently the projector was left powered up during teaching quarters (only the lamp shut off overnight), but down over the breaks between them, and most recently, throughout the pandemic. They want to upgrade it to an IMS within the next 6-12 months, and are happy to leave the projector powered up (apart from brief shutdowns for planned maintenance) until then.

IMHO, that is the most sensible decision. When Dolby would re-cert those things for an insignificant sum (in the context of the running costs of a movie theater), it made sense to take the risk if the batteries were really old; and we had loaners in case we accidentally bricked one, to cover the period while it was out for repair. We don't have those loaners anymore (we sold our last ones in the last few months, to customers whose IMBs went bad), and so I think the most sensible strategy is to keep the survivors in service powered up as near to permanently as possible, until their owners can upgrade the equipment. Obviously, that is easier said than done at present, both because of the semiconductor shortage, and the effect of the pandemic on the movie theater industry.

[Steve Guttag]

A trick there is...the in avoidable power down do to power outage or projector service. You never know if the next one is the one that takes it out. The other thing is if, as I've been told, changing the battery with the card powered up doesn't affect one's chances of a successful battery swap, then how does leaving the projector powered up prolong its life? My guess is that they are wrong and there is a degree of projector power that is holding the certificate. I was going to still use the temporary battery for the swap but the idea was to have that buffer of full board power while the batteries were being messed with. I don't think they ever tried doing it powered. We have both the Dolby Dock and the USL EDP-100 (just the edge connector with power supply) that can leave the board powered during the change. I don't think I'll ever be able to test my theory since we now have two classes of CAT745s...have the 10-year soldered in battery...have lost certificates (just ran into two of those this week).

[Carsten Kurz]

Do they run this projector on a UPS? Because a powerglitch could become a desaster in this case. Still don't understand why Dolby 'feels' incapable of reserialising these IMBs. They are even working on a field procedure to extend the cert life of Dolphin based IMBs - what actually could be so complicated to keep the re-serialisation process for the CAT745 going?

[Elia Orselli]

what actually could be so complicated to keep the re-serialisation process for the CAT745 going?

Moreover: QSC/USL is still able to remotely repair CMS-2200 with internal certificates expired with a patch file...

[Brad Miller]

Ah yes. This reminds me of all the unnecessary bs we used to have to deal with when those Century and Simplex projector batteries would fail and the auditorium would be down.

Remember kids, digital is perfect!

[Mark Gulbrandsen]

GDC can also reset them, but the media black has to go back to them to have it done,,, A lot of this is because hof the DCI rules set in stone.

[Leo Enticknap]

If I understand the situation correctly, a media block certificate that is about to expire can be renewed in the field, as long as the renewal is done while the existing one is still valid; but not after it has actually expired, or if it is lost due to a FIPS enclosure tamper or battery discharge.

...how does leaving the projector powered up prolong its life? My guess is that they are wrong and there is a degree of projector power that is holding the certificate.

I suspect the latter. Dolby claim that the CR2477N batteries should be replaced every three years, but yet I've encountered cat745s over double that age, still with their OEM batteries, and still OK. Either their recommendation was wildly pessimistic, or mains power is maintaining the certificate memory when the IMB is powered up.

[Kevin Fairchild]

Moreover: QSC/USL is still able to remotely repair CMS-2200 with internal certificates expired with a patch file...

Now that Dolby refuses to re-serial the CAT745, I wish QSC/USL would be willing to offer than as a service.. The CAT745 and CMS-2200 (without the storage board) are essentially the same IMB, right? USL manufactured the IMB so they should know how.

[Leo Enticknap]

Right. The only hardware difference I'm aware of is that the USL IMB has a daughterboard on the top with three SSDs on it.

[Steve Guttag]

They started off the same but the CMS2200 is a different piece of hardware. For instance, it doesn't have the sundial version of the secure clock. I suspect that there are security reasons why QSC couldn't load a certificate into a Dolby IMB. I also wonder how long QSC will support the CMS-2200 since they are out of the server market. Did they ever make any CMS-2200s or were they all left-overs from USL? To the best of my knowledge, the CMS-5000 was 100% recalled.

[Leo Enticknap]

In hindsight, killing the Q-Sys IMS was a straw in the wind that QSC was retrenching from the cinema market. Even though they had the USL hardware to begin with, they must have sunk significant R & D resources into developing it into the Q-Sys IMS. Presumably attempts were made to secure some decent launch orders, but they found that they simply couldn't prize market share away from Dolby, GDC, and Barco. We were loaned a demo unit to experiment with and provide feedback on when it first came out: my impression was that it was promising, but needed more work - especially the plugin.

[Steve Guttag]

It became clear, late, to me, that the CMS5000 was the "prize" that QSC seemed to want from USL. I figured that the ADA stuff would be up there since every theatre is legislated to have that and there are not many players in the game...with the Doremi/Dolby offering having distinct disadvantages in its offering. I double that the JSD stuff brought much to the table as their DPM stuff would satisfy that market but so long as sales were up, it wasn't a big deal to keep them going...until the chip factory burned to the ground.

I believe you are correct Leo, they must have sunk a fortune into the CMS5000 for it to not pan out. It's only way into cinemas, in my opinion, would have been via Q-SYS...except Q-SYS is far from an established cinema standard "go-to" system. It is likely more of a niche that people like me yap about and just love the flexibility it brings. But even a Q-SYS fan like me would not necessarily jump to the CMS5000. If I have customers that like Dolby or GDC, they are going to want to stick with those brands (I have no customers that love the OEM stuff by Barco or Christie. It isn't that they hate them (well, maybe the IMB-S2, if any are left), but I don't see any brand loyalty there nor wishing the other server companies were like them.

So, the CMS5000 would have had a slow-slog into the cinema industry. What looked promising to me was the UI that seemed to take many cues from "Show Manager" of the DSS fame...too bad that the IMS series couldn't do likewise. Their closest attempt has been on the IMS3000 to have a calendar view for scheduling on the more recent (over a year now) software.

I think C19 killed their cinema division. If you had "cinema" in your title, the outlook for your long-term future in QSC was like a red-shirt in Star Trek TOS.

[Leo Enticknap]

Agreed on all fronts. The market (for servers and media blocks) was mature. QSC were never going to be able to grow it, leaving the only option being to try to claw market share away from the others. They were up against experience and brand loyalty. As you write, the CMS-5000's "killer app" was Q-Sys integration, but what Q-Sys brings to the table is only really an attraction (and worth the investment) for arthouses, mixed use venues, and relatively sophisticated screening rooms. Once you've put cores and double redundant audio LANs into a building and DCIOs (which, just for that one unit, aren't a helluva lot less than a CP950) into every audio rack of a 15-plex, that's a lot more pricey than traditional audio processors, and a typical 15-plex isn't going to benefit much from the extra functionality.